Emilio J. Juarez-Perez

Five experiments running on ParaSol — and five free slots

2026-05-13T00:00:00+00:00

ParaSol — rooftop outdoor PV testing platform at INMA (CSIC – Universidad de Zaragoza). Each sample is identified by its partner’s logo placed next to it.

A few weeks ago I shared here that a perovskite solar cell on porcelain stoneware had crossed 430 days of continuous outdoor operation on our ParaSol platform — part of the BONIFACE project with Gres Aragón.

That cell is not alone up there.

ParaSol — the rooftop outdoor PV testing platform of the Open Solar Stability Lab at INMA (CSIC – Universidad de Zaragoza) — is currently hosting five experiments from five different organisations. Each sample sits next to its partner’s logo, so the picture identifies who is who.

1) Perovskite-on-porcelain-stoneware cells. BONIFACE project, with Gres Aragón (Grupo SAMCA). The 430+ day single cell and a module consisting of four single cells connected in series.

2) A perovskite module of more than 700 cm² from imec / EnergyVille.

3) Perovskite solar cells fabricated with green solvents. Project GENIAL (AEI Generación de Conocimiento), Universitat de València and Universidad de Zaragoza.

4) Our own perovskite cells encapsulated with Eversolar® UV-curable resins from Everlight Chemical.

5) A paraffin-based photothermochromic film developed at ICN2, with Futurechromes — a spin-off dedicated to advanced photochromic materials that are also being tested on the platform.

At the heart of it all sits Perovskino, our open-source MPPT tracker designed specifically for perovskite devices and the same hardware that quietly logged those 430 days of the BONIFACE cell. We are now also moving Perovskino through Universidad de Zaragoza’s spin-off route, to make it available beyond our own lab.

ParaSol also runs pyranometer, anemometer, humidity sensors, webcam and full data logging — everything needed to run a real-world degradation campaign rather than an indoor accelerated test.

We have five free slots in the cabinet right now. We can host anything from single cells up to modules with Voc up to 150 V. Typical campaigns last one year, or until we have enough data to extrapolate T80 — whichever comes first. At the end you get the full time-resolved dataset and a short report.

If your group, company or spin-off is curious to know whether your devices survive a real Iberian summer, drop me a line.

Acknowledgments

These collaborations are possible thanks to Ainhoa Bilbao (Gres Aragón), Arantxa Aguirre (imec / EnergyVille), Teresa S. Ripollés, Cristina Momblona and Noemí Farinós Navajas (project GENIAL, Universitat de València · Universidad de Zaragoza), Gordon Chao (Everlight Chemical), Claudio Roscini (Futurechromes) and the ICN2 team — and to my own group at the Nanostructured Films and Particles (NFP) group at INMA.

Get in touch

If you would like to test your devices on ParaSol, write to me at ejjuarezperez@unizar.es. We can host anything from single cells up to modules with Voc up to 150 V; campaigns typically run for one year or until enough data are accumulated to extrapolate T80, and at the end you receive the full time-resolved dataset and a short report.

OSS Lab Telegram channel

This work is part of the BONIFACE project (CPP2022-009766), a public-private collaboration between the Institute of Nanoscience and Materials of Aragón (INMA, CSIC – University of Zaragoza) and Gres Aragón (SAMCA Group), funded by MCIN/AEI/10.13039/501100011033 and by the European Union — NextGenerationEU/PRTR.

A Perovskite Solar Cell on Ceramic Has Been Running Outdoors for Over a Year

2026-03-16T00:00:00+00:00

In December 2024, we installed two solar cells on our ParaSol outdoor testing platform on the rooftop of the INMA building in Zaragoza: a conventional silicon reference cell and a perovskite cell fabricated on porcelain stoneware — the same ceramic material widely used in building facades and floors.

The question was straightforward: can a perovskite solar cell on a construction-grade ceramic substrate survive real outdoor conditions?

As of today, the answer is yes — for over 430 days and counting.

What the cell has endured

Zaragoza’s continental climate is not kind to solar devices. Over the course of more than 14 months of continuous outdoor operation, the cell has been exposed to:

Device surface temperatures exceeding 60 °C during summer
Relative humidity swings from 40% to over 90%
Cumulative solar irradiation above 2000 kWh/m²
Rain, wind, dust, and the full cycle of seasons from winter to winter

The figure below shows the daily efficiency of both the silicon reference cell (left) and the perovskite-on-ceramic cell (right), together with the temperature and humidity conditions recorded throughout the entire period.

Figure 1: Stability data for silicon and perovskite-on-ceramic cells over 430+ days.

Why this matters

Perovskite solar cells are one of the most promising photovoltaic technologies: they can be fabricated at much lower temperatures than silicon (which requires processes well above 1000 °C), with significantly lower energy consumption and carbon footprint. However, their long-term stability under real outdoor conditions has been their biggest question mark.

Most published stability data comes from laboratory testing — controlled environments, accelerated aging protocols, or encapsulated devices under idealized conditions. Real outdoor data, measured day after day through actual weather, is still scarce. This result contributes to filling that gap.

Why ceramics?

Porcelain stoneware is one of the most widely used materials in construction — facades, ventilated walls, rooftops, and floors. It is durable, weather-resistant, and produced by a well-established industrial sector, particularly strong in Spain.

If perovskite photovoltaic technology can be reliably integrated into ceramic substrates, it opens a path toward building-integrated photovoltaics (BIPV) at scale: building envelopes that generate electricity without requiring dedicated panel installations. Imagine facades and rooftops that are both architectural elements and power generators.

How we track it

All data is collected continuously using Perovskino, our open-source Arduino-based galvanostatic maximum power point tracker, specifically designed for perovskite solar cells. Perovskino addresses the hysteresis effects that make conventional MPPT algorithms unreliable for perovskite devices. The design has been published in Cell Reports Physical Science and STAR Protocols.

The ParaSol platform integrates multiple Perovskino units with environmental sensors (temperature, humidity, irradiance, wind) and automated data pipelines for continuous monitoring.

What’s next

We continue working to improve both efficiency and durability. This milestone — over one year of continuous outdoor operation — is an important step, but the road to commercial viability requires much longer demonstration periods and further optimization.

We are also expanding collaborations with international groups to replicate outdoor testing in different climates, which will be essential to validate perovskite stability across a range of real-world conditions.

OSS Lab Telegram channel

Stanford rankings

2026-02-22T15:52:10+00:00

Updated: 22 Feb 2026

Currently, there are several updates for the Stanford ranking Updated science-wide author databases of standardized citation indicators:

Version 1 dataset (Jul 06, 2019) at https://doi.org/10.17632/btchxktzyw.1
Version 2 dataset (Oct 08, 2020) at https://doi.org/10.17632/btchxktzyw.2
Version 3 dataset (Oct 19, 2021) at https://doi.org/10.17632/btchxktzyw.3
Version 4 dataset (Oct 10, 2022) at https://doi.org/10.17632/btchxktzyw.4
Version 5 dataset (Nov 03, 2022) at https://doi.org/10.17632/btchxktzyw.5
Version 6 dataset (Oct 04, 2023) at https://doi.org/10.17632/btchxktzyw.6
Version 7 dataset (Sep 16, 2024) at https://doi.org/10.17632/btchxktzyw.7
Version 8 dataset (Sep 19, 2025) at https://doi.org/10.17632/btchxktzyw.8

There are two types of classification. The most relevant is the list of scientists in the top 2% of the world which provides standardized information on citations, h-index, co-authorship adjusted hm-index, citations to papers in different authorship positions and a composite indicator for their entire career and another ranking of scientists in the top 2% of the world but only considering the latest one year time frame.

I noticed that I appear in the ranking considering single years (but no in the list of career-long impact).

Ranking Stanford TOP 2% Scientists for the single year 2017: position 100578 out of 106369.
Ranking Stanford TOP 2% Scientists for the single year 2019: position 75928 out of 161442
Ranking Stanford TOP 2% Scientists for the single year 2020: position 77644 out of 190064
Ranking Stanford TOP 2% Scientists for the single year 2021: position 67386 out of 200196.
Ranking Stanford TOP 2% Scientists for the single year 2022: position 81507 out of 210198.
Ranking Stanford TOP 2% Scientists for the single year 2023: position 90790 out of 223153.
Ranking Stanford TOP 2% Scientists for the single year 2024: position 97541 out of 236313.

Calibrating our solar irradiance sensor for the ParaSol Platform

2026-02-13T08:35:10+00:00

We monitor perovskite solar cells outdoors for months. To tell if a cell is degrading, we need accurate irradiance data. A 5% error in irradiance means a 5% error in calculated efficiency which is enough to confuse real degradation with a bad measurement day.

We use a small (1.18 cm²) commercial monocrystaline silicon cell in short circuit mode assuming that there is a direct proportional constat to translate mA photocurrent from the cell measured by Perovskino to W/m² power irradiation. But it needs calibration as we observed that calibration changes over time.

Three ways to know the irradiance

We work with three complementary data sources:

The silicon cell is our main sensor. We measure its short-circuit current every 3 seconds. Current is proportional to irradiance, but we need the conversion factor (mA → W/m²). It’s cheap, fast, and has a spectral response similar to the cells we’re testing.

The pyranometer measures total irradiance across visible and near-infrared. It’s the meteorological standard equipment usually disposed in horizontal plane. Our pyranometer is on plane as silicon cell and the output signal is offered in mV (0-5000 mV) ideal for the INA219 embeded in the Perovskino.

CAMS data (Copernicus Atmosphere Monitoring Service) provides satellite-estimated irradiance with one-minute resolution. It is free, more or less global coverage and uses sophisticated atmospheric corrections. The limitation: it can’t see small clouds or local shadows in our horizon.

Our strategy is to use CAMS as a long-term reference to calibrate the silicon cell and the pyranometer when available, and track how the calibration evolves.

Figure 1: Three complementary data sources for irradiance measurement. The silicon cell and the pyranometer provide high-frequency irradiance local data with our horizon, CAMS offers satellite-based reference, serves as ground-truth validation.

The calibration method

The idea is simple. On a clear day, integrate the sensor current, compare it to the energy CAMS predicts for POA 30º, then calculate the conversion factor.

In practice, there are subtleties. Early morning and late afternoon add noise: low solar angles, building shadows, and the silicon’s spectral response deviates from the actual solar spectrum. So we use only midday hours (typically 10:00 - 16:00) for the fitting and require clear-sky conditions with mean absolute error below 3% (30 W/m² MAE). The algorithm finds the factor that minimizes the error difference between measured irradiance (current × factor) and CAMS irradiance.

Figure 2: Calibration on a clear day. Top panel shows calibrated sensor signal vs CAMS reference. Bottom panel shows error between both traces. The shaded region marks the midday window used for fitting.

The problem with a single factor

Here’s where it gets interesting. When we calculated the calibration factor daily over 18 months, we didn’t get a constant. The factor drifted.

Date	Factor
June 2024	21.0
January 2025	19.5
September 2025	24.5

That’s a 25% variation too large to ignore.

Some variation is noise: cloudy days where CAMS and the sensor see different things, dust accumulation between cleanings, statistical uncertainty. But there’s also a systematic drift that we attribute to encapsulation aging. The epoxi layer protecting our silicon cell yellows and delaminated slightly over time reducing transmission.

Using a single average factor would introduce systematic errors: underestimating irradiance in summer 2024, overestimating it in late 2025. For stability studies spanning months, this affects the efficiency calculations.

Figure 3: Calibration factor evolution over 18 months. Red points are high-quality days (MAE < 3%) used for the piecewise function. The blue line shows the piecewise linear interpolation.

The solution: a time-varying calibration function

Instead of one factor, we now use a piecewise linear function that interpolates between calibration points. The concept:

Select high-quality calibration days (clear sky, MAE < 3%)
For each, record the date and optimal factor
For any measurement timestamp, interpolate linearly between the two nearest calibration points
Extrapolate using edge values for dates outside the calibration range

This approach has several advantages:

Tracks slow drift from encapsulation aging or soiling
Adapts to seasonal effects in spectral response
Backward compatible: a single point reduces to a constant factor
No wild extrapolation: edge values are used conservatively

Why not just use CAMS?

CAMS is great for calibration and long-term validation, but has limitations for real-time monitoring:

Temporal resolution: 1 minute vs our 3 seconds
Spatial resolution: ~5 km pixels miss local shadows and small clouds
Latency: data available hours to days after measurement
Availability: occasional gaps and outages

The local sensor provides continuous, high-frequency data. CAMS keeps it honest.

The workflow

Our current system works like this:

Monthly: Run calibration script on recent clear days, add good points to the JSON
Daily: Export scripts automatically apply piecewise calibration to irradiance data
On-demand: Analysis scripts use the same calibration for efficiency calculations

Figure 4: Calibration workflow. CAMS and sensor data feed into periodic calibration runs that update the JSON file. All analysis and export scripts read from this shared calibration, ensuring consistency across the entire data pipeline.

The calibration code is part of our ParaSol outdoor testing platform. If you work on PV characterization and want to compare outdoor stability data across different climates, get in touch.

Solar Cell Stability Data Visualization in Telegram

2026-01-25T08:35:10+00:00

Figure: The new data panel

Rethinking Solar Cell Stability Data Visualization: From Real-Time Noise to Long-Term Insight

We have been monitoring perovskite solar cells outdoors with the ParaSol platform for over three years now. During this time, the reporting system has evolved according to day-to-day needs. What started as an hourly real-time diagnostic tool has transformed into a system oriented towards long-term trend analysis. In this post, I describe the most relevant changes in how we now present the data in our Telegram channel.

Reporting Frequency: From Hourly During Daylight to a Single Daily Figure

The most significant change affects how often reports are generated. Until now, the system produced an updated graph for each cell every hour, from 8:00 AM to 10:00 PM. This meant 14 daily reports per device, which made sense during the setup and debugging phases when we needed to detect problems in near real-time from a mobile phone without being directly plugged into the raw data stream (6–7 data rows per second per device) on a computer terminal.

However, once the system runs reliably, this frequency becomes excessive. It generates an amount of data that is difficult to review and consumes processing resources unnecessarily. From now on, a single daily report is generated around 9:00 AM, summarizing all activity from the previous day. This approach is much more manageable for long-term monitoring and allows more attention to be devoted to each report instead of getting lost among dozens of nearly identical graphs.

Panel 2: Instant Power with Context

Figure: The new data panel 2

Previously, the instant power graph showed all data from the last 3 days without distinction. This included both periods in MPPT mode (maximum power point tracking) and moments when the tracker performed JV sweeps to characterize the cell. The result was a confusing mix where the peaks and valleys from JV sweeps contaminated the visualization of actual performance.

The new version filters exclusively the data corresponding to MPPT mode and, additionally, overlays the solar irradiance measured by the reference detector (a single Si solar cell monitoring short-circuit current and a commercial pyranometer—more on this in a future post). This makes it straightforward to correlate power drops with passing clouds or compare performance between days with different illumination levels.

Panels 4, 5, 6, and 7: JV Parameters Without Noise

Figure: The new 4–7 data panels

In the early days of ParaSol, we only showed panels 0–3, excluding any reference to JV sweeps performed between MPPT modes. However, this summer, at the request of our colleagues from EnergyVille (Belgium), who kindly provided two large perovskite modules, we began reporting this data.

The characteristic parameters of JV curves (open-circuit voltage, currents, fill factors, and maximum power) are fundamental for evaluating the state of a solar cell. In the previous version, these parameters were extracted from each measured JV curve and represented as continuous time series.

The problem is that, as weeks or months of data accumulate, these graphs become unreadable. The natural dispersion between measurements, variations due to temperature and irradiance, and the simple fact of having hundreds or thousands of points generate noise that completely obscures the degradation or stability trends we actually care about.

The solution has been to select only the best JV curve of each day, with “best” defined as the one delivering the highest power. This reduces each time series to one point per day, drastically cleaning up the noise and revealing the underlying trends. It is now possible to see at a glance whether Voc, Vmpp, Jsc, or Jmpp is gradually declining, or if the fill factor remains stable after months of exposure.

Panels 8 and 9: Visible Hysteresis

Figure: The new 8 and 9 data panels

Perovskite cells exhibit hysteresis: the JV curve measured sweeping from low to high voltage (forward) does not match the one measured in the opposite direction (backward). This phenomenon, related to ion migration in the material and charge-selective contacts interfacing the perovskite, is one of the most studied characteristics of this technology.

In the previous system, both sweeps were processed together as if they were a single curve. When sorting the points by voltage for plotting, the result was a zigzag pattern that did not correspond to any real physical curve and made interpretation difficult.

Now the system correctly identifies and separates both sweeps. In the J–V and P–V curve graphs, the most efficient curve (typically backward in perovskites, but not always, as hysteresis can decrease or be mitigated over time) appears as a solid line, while its companion is shown as a faint dashed line. This allows direct visualization of the hysteresis magnitude and how it evolves with time or measurement conditions.

Panels 10 and 11: Temporal Context of the Best JV

Figure: The new 10 and 11 data panels

The last two panels now show something that was not previously available: the cell’s behavior in the minutes immediately before and after the best JV measurement of the day.

Why is this useful? Because it allows evaluation of whether the cell was operating stably when the JV sweep was performed or if, on the contrary, it was in a transient state. It also shows how the cell responds after the sweep: whether it immediately recovers its previous operating point or takes time to stabilize. This type of information is relevant for understanding hysteresis and degradation mechanisms under real operating conditions.

If you’re interested in following our perovskite stability experiments in real time, feel free to join our Telegram channel. We share daily updates on device performance, new measurement features, and occasional insights from our outdoor testing campaigns. And if you know colleagues working on perovskite stability or outdoor photovoltaic monitoring, we’d appreciate it if you spread the word—the more eyes on the data, the better the science!

La Estrella de la Muerte que se Alimenta del Sol: Fotobaterías en la Noche de los Investigadores 2025

2025-10-17T08:00:00+00:00

La Estrella de la Muerte que Necesita el Sol: Enseñando Fotobaterías con Star Wars

El pasado 26-27 de septiembre, los grupos HYMAT y NFP del Instituto de Nanociencia y Materiales de Aragón (INMA) llevaron a la Plaza del Pilar de Zaragoza una experiencia única que combinó ciencia con la épica de Star Wars. Nuestra misión: enseñar al público cómo funcionan las fotobaterías usando una réplica en miniatura de la Estrella de la Muerte.

El equipo de voluntarios del INMA listo para la batalla (científica)

El Desafío del Gran Moff Tarkin: Mantener las Defensas Activas

La premisa era simple pero educativa: ¿Puede el Gran Moff Tarkin mantener operativos los sistemas de defensa de la Estrella de la Muerte mientras orbita un planeta? Para ahorrar cristales kyber (y enseñar conceptos de energía renovable), nuestro sistema de defensas (LEDs) debe mantenerse activo usando una pequeña estrella con ciclos de iluminación de 2 minutos.

Los 4 Sistemas de Alimentación Propuestos

Planteamos a los visitantes cuatro posibles soluciones energéticas:

Solo Celda Solar ❌
- Problema: Energía intermitente y sin defensas durante la noche orbital
Solo Batería de Li-Ion ❌
- Problema: Necesita recarga externa (¿dónde está el puerto USB en el espacio?)
Celda Solar + Batería (conectadas solo en luz) ✅
- ¡Solución correcta! La fotobatería ideal
Celda Solar + Batería (siempre conectadas) ❌
- Problema: La celda solar actúa como LED infrarrojo en oscuridad, drenando energía

Esquema de la Estrella de la Muerte con fotobatería mostrando las tres situaciones posibles en luz/oscuridad con y sin superdiodo

La Ciencia Detrás de la Fuerza (Fotovoltaica)

¿Qué es una Fotobatería?

Una fotobatería es un dispositivo que combina la captación de energía solar y el almacenamiento en una única unidad integrada. En los sistemas tradicionales, los paneles solares y las baterías son componentes separados conectados por cables. En una fotobatería verdadera, ambas funciones ocurren en el mismo dispositivo. Nuestra Estrella de la Muerte es un modelo educativo que demuestra el principio de funcionamiento: aunque la celda solar y la batería todavía están físicamente separadas (como en los sistemas actuales), ilustra perfectamente por qué necesitamos la gestión inteligente de la conexión entre ambos componentes. Es un paso intermedio hacia las fotobaterías completamente integradas que estamos desarrollando en el laboratorio, donde un único apilamiento de capas de material podrá captar luz y almacenar energía simultáneamente.

El Problema del “LED Vampiro”

Durante la fase oscura de la órbita, descubrimos un fenómeno fascinante: las celdas solares se comportan como LEDs infrarrojos cuando no reciben luz, emitiendo radiación y drenando la batería. Por eso necesitamos nuestro “superdiodo” - un componente que desconecta inteligentemente la celda solar durante la oscuridad además de evitar las pérdidas de energía que produce un diodo convencional.

Tecnología Real para un Imperio Imaginario

El Simulador Solar Orbital

Utilizamos nuestro simulador solar programable desarrollado específicamente para replicar los ciclos luz/oscuridad que experimenta un satélite en órbita. Con una lámpara halógena dicroica controlada por Raspberry Pi Pico, podemos simular:

Órbitas LEO: ~90 minutos con 60 minutos de luz y 30 de oscuridad.
Órbitas personalizadas: Ajustables para cualquier escenario. En la noche de los investigadores usamos un ciclo de 2 minutos de luz y oscuridad.
Transiciones suaves: Simulando amaneceres y atardeceres orbitales.

Monitorización en Tiempo Real

El sistema incorpora nuestro tracker MPPT “Perovskino” para monitorizar el estado de carga de la fotobatería, específicamente:

Sensor INA219: Mide voltaje (SOC, estado de carga) en tiempo real.
Arduino con conectividad: Recolecta y transmite datos al chromebook.
Interfaz web temática: Gráficos al estilo Star Wars mostrando la carga/descarga
Pantalla en vivo: Los visitantes podían ver cómo la batería se cargaba con luz y se descargaba en oscuridad llevando la imagen del chromebook a una pantalla más grande via HDMI.

Mira este video con el setup en acción:

⬆️ Click en la imagen para ver el video: La Estrella de la Muerte con fotobatería en acción

Making Of: Construyendo la Estrella de la Muerte

La construcción de nuestra Estrella de la Muerte educativa fue todo un proyecto de ingeniería con mucha prueba-error, encontrar el número adecuado de LEDs y unas resistencias adecuadas que no drenaran toda la batería en menos de dos minutos:

Del modelo 3D a la realidad: integrando electrónica en una esfera de 12 cm

Esquema interno de la Estrella de la Muerte mostrando la integración de la fotobatería

Componentes Clave:

Esfera de 12 cm: Impresa en 3D y pintada para parecer la Estrella de la Muerte
Modulo solar de silicio: constituido por 6 celdas de Si monocristalino soldadas en serie con alambre que permitía adaptarse con facilidad a la superficie curva de la esfera y a máxima iluminación producía > 3V de Voc necesarios para cargar la batería.
Batería LiFePO4: recargable y comercial, de 3.4V nominal.
LEDs: situados en diferentes posiciones de la esfera y divididos en tres segmentos que representan los “sistemas de defensa” visibles
Electrónica de control: Microcontrolador extraido de un juguete que permitía encender/apagar todos los segmentos a la vez o por separado a distintas frecuencias de intermitencia que afectan al consumo.
Maletín de transporte: Todo organizado y listo para el evento

El dispositivo preparado para su transporte: todo organizado y listo para el evento

El Impacto: Ciencia que Conecta

Visitantes Entusiasmados

Durante los dos días del evento, según datos oficiales de Ayuntamiento y Policia de Zaragoza por la carpa de la Ciencia pasaron 38.000 personas, en los dos días de apertura y 3 sesiones, cientos de personas de todas las edades participaron en nuestra actividad. Los más pequeños quedaban fascinados viendo cómo los LEDs se apagaban cuando “el planeta bloqueaba el sol”, mientras que los adultos hacían preguntas técnicas sobre aplicaciones reales y el misterioso superdiodo, muchos desconocían que las celdas solares se comportan como un LED en oscuridad si tienen una fuente de energía que los alimente.

Visitantes en nuestro stand

Tres Willrow Hood con su Camtono llenito de Beskar y un residente de Narkina 5

Conceptos Aprendidos:

Energía renovable: La importancia del almacenamiento para fuentes intermitentes
Electrónica básica: Cómo funcionan los LEDs, baterías y celdas solares
Ingeniería espacial: Los desafíos energéticos de los satélites reales
Innovación: Las fotobaterías como tecnología emergente

Aplicaciones del Mundo Real

Mientras los niños se divertían salvando la Estrella de la Muerte, también explicábamos aplicaciones reales de las fotobaterías:

En el Espacio:

Satélites CubeSat: Optimización del peso con sistemas integrados
Misiones a Marte: Rovers que necesitan sobrevivir largas noches marcianas
Estación Espacial Internacional: Gestión eficiente de ciclos de 90 minutos

En la Tierra:

IoT remoto: Sensores ambientales autónomos
Dispositivos médicos: Implantes que se recargan con luz a través de la piel
Electrónica portable: El futuro de dispositivos sin cables
Almacenamiento en red: Soluciones para energía solar doméstica

La Ciencia Continúa: Proyectos de Investigación

Esta actividad divulgativa está respaldada por investigación puntera en el INMA:

Proyecto SOLiBAT (CNS2023-145197)

Desarrollo de nuevas arquitecturas de fotobaterías basadas en materiales emergentes, financiado por MICIU/AEI y la Unión Europea NextGenerationEU/PRTR. Proyectos que hacen posible esta investigación: Solibat

Proyecto VOLTA (PID2022-140516OB-I00)

Investigación en sistemas de almacenamiento energético híbridos, cofinanciado por FEDER, UE. Proyectos que hacen posible esta investigación: VOLTA

Recursos Educativos

Para Educadores:

Si quieres replicar esta actividad en tu centro educativo, hemos preparado:

Guía de construcción del simulador solar
Esquemas electrónicos de la fotobatería (disponibles por solicitud)
Presentación didáctica adaptable a diferentes niveles

Para Makers:

Código del Perovskino para monitorización disponible en GitHub
Lista de componentes y proveedores
Modelo 3D de la esfera

Reflexión Final: Cuando la Ciencia Ficción Inspira Ciencia Real

Lo más gratificante de esta experiencia fue ver cómo una narrativa de ciencia ficción puede hacer accesibles conceptos científicos complejos. Desde el niño de 6 años que entendió que “la Estrella de la Muerte necesita batería para cuando no hay sol” hasta el ingeniero jubilado que nos preguntó sobre la eficiencia de conversión de nuestras celdas, todos se llevaron algo valioso.

Las fotobaterías representan el futuro del almacenamiento energético integrado, y qué mejor manera de explicarlo que con una galaxia muy, muy lejana que todos conocemos y amamos.

Que la fuerza (fotovoltaica) os acompañe. ⚡🌟

Agradecimientos

Esta actividad fue posible gracias a:

Todo el equipo de voluntarios del INMA que dedicaron su fin de semana a la divulgación
El Gobierno de Aragón y Aragón Investiga por organizar la Noche Europea de los Investigadores
Los proyectos SOLiBAT y VOLTA por financiar esta investigación
Lucasfilm (indirectamente) por crear un universo que sigue inspirando a nuevas generaciones de científicos

¿Interesado en nuestras investigaciones sobre fotobaterías? Síguenos en nuestro canal de Telegram y mantente al día con los últimos avances del OSSLab del INMA.

Autor: Emilio J. Juarez-Perez, Marta Haro Remón
Grupo de investigación: NFP - Nanostructured Films & Particles y HYMAT - Hybrid Materials for Optoelectronics
Instituto: INMA (CSIC-Universidad de Zaragoza)

Heraldo de Aragón destaca nuestra investigación en fotobaterías y MOFs

2025-07-20T10:00:00+00:00

Nuestra investigación en fotobaterías destacada en Heraldo de Aragón

¡Excelentes noticias! 📰 El Heraldo de Aragón ha publicado un extenso artículo sobre el trabajo de Isabel Ciria Ramos (grupo HYMAT-INMA) en su tesis doctoral, destacando dos líneas de investigación fundamentales: redes metal-orgánicas (MOFs) como ánodos para baterías de litio-ion y el desarrollo de fotobaterías.

Artículo original: Heraldo de Aragón - Llegan las fotobaterías: investigadores de Unizar trabajan en baterías de litio que se cargan con luz solar

Trabajo doctoral destacado en el HYMAT-INMA

La investigación, realizada en el grupo HYMAT del Instituto de Nanociencia y Materiales de Aragón (INMA), aborda dos desafíos críticos en el almacenamiento de energía:

🔋 MOFs para superar las limitaciones del grafito

Investigación sobre redes metal-orgánicas que podrían reemplazar los ánodos de grafito actuales. Estos materiales ofrecen:

Mayor densidad de energía por unidad de masa
Rangos de voltaje más seguros
Múltiples sitios para almacenar iones litio

Publicación: “Electrochemical Performance of M(dca)₂pyz (M= Fe, Co, and Ni) MOFs as Sustainable Anodes in Lithium-Ion Batteries”

Journal of Materials Chemistry A, Vol. 12, pp. 20215-20228 (2024)
DOI: https://doi.org/10.1039/d4ta02137a

⚡ Fotobaterías: carga directa con luz solar

Desarrollo de una fotobatería con forma de botón más pequeña que dos monedas de 5 céntimos apiladas, que se recarga únicamente con luz sin necesidad de cables ni conexión a la red.

Publicación: “Solar Energy Storage Using a Cu₂O-TiO₂ Photocathode in a Lithium Battery”

Small, pp. 2301244 (2023)
DOI: https://doi.org/10.1002/smll.202301244

Impacto real de las innovaciones

Como destaca el artículo, estas investigaciones tienen implicaciones directas en la vida cotidiana:

🚗 Vehículos eléctricos: Los MOFs podrían aumentar la autonomía sin incrementar el peso de las baterías, reduciendo las paradas para recargar en viajes largos.

🏥 Dispositivos médicos: Las fotobaterías permitirían dispositivos implantables que no necesiten cambio de batería o sensores ambientales que funcionen indefinidamente con luz natural.

🌍 Sostenibilidad energética: Contribución a un modelo energético más sostenible, descentralizado y accesible, reduciendo la dependencia de materiales importados.

Reconocimiento del trabajo doctoral

El artículo destaca especialmente el trabajo de Isabel Ciria Ramos, graduada en Química y doctoranda en el programa de Química Física de la Universidad de Zaragoza, bajo la dirección de Marta Haro Remón y Emilio J. Juarez-Perez.

Es especialmente gratificante ver cómo el trabajo fundamental desarrollado en el HYMAT-INMA recibe este reconocimiento mediático, contribuyendo a posicionar la investigación aragonesa en el mapa de la innovación en tecnologías energéticas sostenibles. 🔬⚡

¡Seguimos avanzando hacia el futuro de la energía limpia! 🌞🔋

¿Interesado en nuestras investigaciones? Síguenos para más actualizaciones sobre nuestros avances en tecnologías energéticas.

Temperature milestone at ParaSol platform

2025-06-11T08:35:10+00:00

Yesterday (June 10th) we reached >60°C device temperature for the first time this year at our perovskite solar cell testing platform! 📈

Key observations from our weather station data:

• PARASOL consistently measures 4-5°C higher maximum temperatures than ambient due to a “pot effect” created by the high walls surrounding our rooftop terrace at the I+D+i building (Universidad de Zaragoza, Río Ebro Campus)

• Temperature matching between ambient and device sensors during night time hours with no solar radiation. ☽

• Minimum temperatures show no “pot effect” confirming our hypothesis about the terrace microclimate influence

The graphs show 3 days of instant temperatures (device/ambient/chamber storing electronics) plus power irradiation, alongside AEMET maximum, minimum and average temperature data from Zaragoza Airport for comparison.

The harsh season begins for perovskite cells in Zaragoza! 🔥 We’ll be watching closely to see if we surpass last year’s 66°C peak reached in late July.

This thermal behavior is crucial for understanding real-world performance of our perovskite cells with MPP tracker technology! 🔬⚡

📢 Join our channel for more updates: https://t.me/oss_lab

DIY Solar Simulator: Programmable Light Dimmer for Replicating Orbital Light/Dark Cycles

2025-05-04T08:35:10+00:00

In the world of satellite engineering and research, understanding how components behave under the cyclical light and darkness conditions experienced in orbit is crucial. Professional testing equipment can be prohibitively expensive, but with some basic electronics knowledge, we can build a DIY solution that simulates these conditions remarkably well.

This project represents the latest addition to our laboratory’s integrated research ecosystem, complementing our previous work on the Perovskino MPPT tracker for solar cell characterization. As our team continues exploring novel photobattery systems that combine energy harvesting and storage in unified devices, accurately simulating the unique light/dark cycles experienced in different orbital environments has become essential for testing these emerging technologies under realistic space conditions.

In this post, I’ll share how I built a programmable light dimmer specifically designed to replicate the light/dark cycles experienced by satellites in various orbits using a halogen dichroic lamp.

The Problem: Simulating Satellite Light Conditions

Satellites in different orbits experience varying patterns of light and darkness. For example, the International Space Station in Low Earth Orbit (LEO) experiences approximately 16 cycles of day and night every 24 hours, with roughly 55 minutes of sunlight followed by 35 minutes of darkness in each 90-minute orbit. Satellites in higher orbits have different patterns - some in special sun-synchronous orbits might even experience constant sunlight.

Testing how solar panels, sensors, and other components respond to these lighting patterns is essential for satellite development, but commercial solar simulators are expensive. This is where our DIY solution comes in.

The Solution: A Programmable Light Dimmer

Figure: The light dimmer, unboxed components

Figure: The light dimmer in a box

Our system consists of a Raspberry Pi Pico microcontroller-based dimmer circuit that can control the power output of a halogen dichroic lamp to simulate different lighting patterns. The key features include:

Dual operation modes: Manual power selection or programmable automatic cycles
Pattern flexibility: Support for both sinusoidal transitions (smooth changes) and linear ramps
Complete cycle control: Programmable light intensity and duration of light/dark phases.
Real-time monitoring: LCD display showing current status and parameters
Data acquisition: Light power calibration and voltage/current measurement of solar cells for power analysis using our Perovskino MPPT tracker

Hardware Components

The project uses:

A microcontroller (Raspberry Pi Pico shown in the diagram)
LCD display for user interface
Potentiometer and button for user control (alternatively using a pulsable rotary encoder)
Various basic electronic components (resistors, capacitors, diode, N-mosfet and npn-transistor)
Halogen dichroic lamp (50 W) as the light source
AC adapter and linear voltage regulator to feed lamp and electronics.

How It Works

The system is controlled by a Raspberry Pi Pico running MicroPython code that handles two main modes of operation:

Manual Mode

In manual mode, a potentiometer directly controls the brightness of the halogen lamp. The system reads the analog input, applies a moving median filter to reduce noise, and maps this value to the appropriate power level using a calibrated lookup table. This ensures accurate and consistent brightness control.

The LCD display shows:

Raw ADC value from the potentiometer (0-65535)
Limited ADC value (within operational thresholds)
Calculated power percentage (0-100%)

Automatic Mode

In automatic mode, the system runs programmable light/dark cycles to simulate satellite orbit conditions:

Setup Phase: The potentiometer sets the light/dark cycle time (up to 12 hours), displayed on the LCD in minutes.
Execution Phase: Once started with a button press, the system automatically transitions between light and dark phases:

During the light phase, two transition patterns are available:
- Sinusoidal transition: Uses sine wave functions for smooth, gradual transitions (more natural)
- Linear ramp transition: Uses linear functions for constant rate of change

The LCD display during execution shows:

Current power percentage
Elapsed time in the cycle
Remaining time in the cycle

Power Calibration System

One of the most innovative aspects of this system is its power calibration method. Instead of using a simple linear relationship between PWM duty cycle and perceived brightness (which would result in inaccurate power control), the system uses:

A calibrated lookup table that maps desired power percentages to precise ADC values
Mathematical models that account for the non-linear relationship between electrical power and perceived brightness
Adaptive update intervals that scale based on cycle duration to maintain smooth transitions while preserving CPU resources

This approach ensures that the simulator can accurately reproduce the precise light conditions experienced by satellites in different orbits, making it an effective tool for testing solar panels, sensors, and other light-sensitive components under realistic space conditions.

Power Output Patterns & Transition Types

The graphs above show both the theoretical design patterns (left) and the actual measured light power trace (right) of the system demonstrating how the system produces controlled light patterns with precise timing.

The system supports two primary types of light transitions:

Sinusoidal transition (blue line): Provides smoother power changes at the beginning and end of the ramp, which may better simulate natural light transitions
Linear ramp (red line): Offers constant rate of change, which may be preferred for certain testing scenarios

but other programable transitions as pulse lights or ramp and dewelling stages are also posible.

As shown in the comparison graph, both patterns achieve the same maximum power (100%) and return to 0% at the end of the primary light phase, but their transition characteristics differ significantly between simple linear ramps or sinuosuodial pattern.

Applications for Satellite Testing

This DIY solar simulator is particularly useful for testing:

Solar panel performance under different orbital illumination patterns
Power management systems that need to handle cyclical charging and discharging stages
Photobattery integration
Optical sensors and cameras that must operate in varying light conditions
Thermal cycling effects caused by repeated heating and cooling

By programming different light/dark cycles, we can simulate various orbital characteristics:

LEO satellites (like the ISS): ~90-minute orbits with ~60 minutes of light and ~30 minutes of darkness
Medium Earth Orbit satellites: Longer cycles with different light/dark ratios
Geostationary satellites: 24-hour cycles with seasonal variations in eclipse time
Sun-synchronous orbits: Nearly constant illumination with brief shadow periods

Conclusion

This relatively simple DIY project provides a powerful tool for simulating the light conditions experienced by satellites in various orbits. Whether you’re a hobbyist working on a CubeSat project, a student doing research, or simply curious about satellite conditions, this programmable light dimmer offers an affordable way to replicate space lighting patterns.

The system’s flexibility means it can be easily adapted to simulate specific satellite orbits or testing scenarios. The ability to choose between sinusoidal and linear transitions also allows for more nuanced testing of how components respond to different rates of illumination change.

Have you built similar testing equipment for space-related projects? I’d love to hear about your experiences!

Note: This project involves working with AC line voltage, which can be dangerous. Always take appropriate safety precautions when building and using high-voltage electronic devices.

OSSLab Update 19 Apr 2025: PVK002 Device Removed from ParaSol Platform

2025-04-19T13:32:10+00:00

Update: PVK002 Device Removed from ParaSol Platform

Date: April 19, 2025

We would like to inform that device coded PVK002 has been removed from the ParaSol platform for real-time power tracking due to significant performance degradation.

Technical Device Details

The PVK002 was a MAPbI₃-based perovskite solar cell with HTM-free stack configuration and an active area of 0.64 cm². Unfortunately, its performance has steadily declined since its early operational stages.

Probable Causes of Failure

Initial hypotheses point to:

Possible deficiencies in the encapsulation procedure
Failures in the electrode cable attachments to the device

A detailed post-mortem examination will be conducted in the coming days to precisely determine the origin of the problem.

Image of PVK002 device tracking

Comparison with Twin Device

It is important to highlight that a twin device belonging to the BONIFACE project, with identical perovskite chemical composition and differing only in the encapsulation procedure, continues to perform well as shown below:

Image of BONIFACE device tracking

Contact

Thank you for your interest in our work. If you have any questions or require additional information about this case, please don’t hesitate to contact us via email.

OSSLab Team

Falstad Circuit Simulator: Exporting Oscilloscope Data for Solar Cell Analysis

2025-04-06T08:35:10+00:00

Introduction

The Falstad Circuit Simulator is a powerful free online tool for electronic circuit simulation, offering real-time visualization of electric behavior in circuits. This browser-based simulator stands out for its intuitive interface and animated current flow, making it an excellent resource for students, hobbyists, and electronics enthusiasts.

While more professional alternatives exist (such as SPICE, LTspice, Multisim, or Proteus) with advanced capabilities for industry-level work, Falstad’s accessibility and visual approach make it particularly valuable for educational purposes and quick circuit prototyping.

In this post, we’ll explore an under-documented feature of Falstad: the ability to export oscilloscope data to text files. This functionality allows you to capture simulation results and process them in external graphing programs. As a practical example, we’ll simulate a solar cell equivalent circuit and export the data to generate power versus voltage curves for solar cell performance analysis.

Solar Cell Simulation in Falstad

The animation below shows a dynamic simulation of a solar cell circuit in Falstad demonstrating both the electrical behavior and real-time data visualization:

A direct link for the circuit above running in the circuit simulator is here: https://tinyurl.com/23h9ct2n

The Solar Cell Equivalent Circuit

At the center of the simulation is a GaAsP/GaAs/Ge solar cell equivalent circuit (enclosed in a dashed box) consisting of:

A photocurrent source (13.7mA) representing light-generated current
A diode modeling the p-n junction behavior
A series resistance (Rseries) accounting for internal losses of 1Ω
A parallel shunt resistance (Rshunt) of 40kΩ

The Test Configuration

The circuit is being poled with:

A 1Hz sine wave voltage source that continuously sweeps from -0.6V to +2.6V
Measurement points showing instantaneous values (a voltage source output and one ammeter)
Two strategic “export” points labeled in the circuit: one for voltage measurement at the cell’s positive terminal, another for current measurement through a 1mΩ sensing resistor.

Real-Time Visualization

The simulation displays two oscilloscope windows attached to the sine wave voltage source showing:

Current vs. Voltage (I-V) characteristic curve
Power vs. Time waveform showing fluctuations between -28.2mW and 27.5mW

Another oscilloscope attached to the voltage source output:

Voltage vs. Power (V-P) curve revealing the maximum power point. It is a trick selecting X-Y type and P output although we are interested to obtain the P vs. V curve.

As the animation runs, you can observe the real-time relationship between voltage, current, and power, with the electron flow animation showing current direction changes as the operating point moves through different regions of the solar cell’s characteristic curve.

Using Export Points in Falstad

After running the simulation for 1-2 complete voltage sweeps across the solar cell, follow these steps to extract the data:

Pause the simulation by clicking the “Stop” button
Left-click on the “export” points placed in the circuit
In the dialog that appears, specify the number of data points
The simulator will generate a text file containing the time-series data for that point. Save this .txt file to your local drive
Import the exported data into your preferred graphing software (Excel, Python, MATLAB, QTIplot etc.)

Figure: Graph using QTIPlot

This method allows you to perform more sophisticated analysis than is possible within Falstad’s built-in oscilloscope, including precise maximum power point calculations, fill factor determination, and comparison between different solar cell models.

The Open Solar Stability (OSS) Lab: An Ecosystem for Testing Stability in Emerging Photovoltaics

2025-02-01T08:35:10+00:00

The OSS Lab at the University of Zaragoza provides an open ecosystem for evaluating the operational stability of perovskite solar cells and other emerging photovoltaic technologies. Our mission is to accelerate the development of stable perovskite solar cells by providing open access tools and platforms for long-term stability testing.

The OSS Ecosystem Components

Perovskino: Maximum Power Point Tracker

At the heart of our ecosystem is the Perovskino, an open-source and low-cost maximum power point tracking (MPPT) device specifically designed for perovskite solar cells. The complete building instructions and basic operation protocol are detailed in our recent publication:

Protocol for building and using a maximum power point output tracker for perovskite solar cells

Additionally, we have developed and validated an innovative galvanostatic approach to MPPT that has proven particularly effective for devices exhibiting high hysteresis, as described in:

Enhanced power-point tracking for high-hysteresis perovskite solar cells with a galvanostatic approach

The complete source code and documentation for the Perovskino are available on GitHub: github.com/ej-jp/perovskino

ParaSol: Long-term Stability Testing Platform

ParaSol is our outdoor testing facility located at the University of Zaragoza’s Rio Ebro Campus. This platform allows simultaneous testing of multiple devices under real environmental conditions while tracking their maximum power point performance. The platform provides comprehensive data collection including:

Device performance metrics
Ambient and device temperature
Solar irradiance
Relative humidity

We invite researchers worldwide to test their perovskite solar cells on our ParaSol platform. If you’re interested in having your devices evaluated, please contact us to discuss testing arrangements.

Real-time Monitoring

We believe in transparency and open data sharing. You can follow the real-time performance of devices currently under test through our public Telegram channel: https://t.me/oss_lab

We’re committed to advancing the field of perovskite photovoltaics through open collaboration and data sharing. Join us in our mission to develop more stable and efficient solar cells.

[Contact us for more information or to discuss testing your devices at ParaSol]

Research Recognition Awards 2024-2025

2025-01-26T00:00:00+00:00

I am pleased to share a series of recognitions our research has received recently highlighting the impact and relevance of our work in sustainable energy and materials science.

Research Awards

Re-UNITA Award (June 2024) The University of Zaragoza awarded our research through the Re-UNITA initiative, which promotes open access publication in strategic areas including Renewable Energy, Circular Economy, and Cultural Heritage. Our winning publication Enhanced Power Point Tracking for High Hysteresis Perovskite Solar Cells with a Galvanostatic Approach introduces an innovative power-tracking algorithm and cost-effective hardware for perovskite solar cells. This development addresses critical challenges in maximizing power generation from these next-generation solar devices, particularly for stable triple-mesoscopic hole-transport-material-free cells. The research emphasizes practical implementation by providing open-source hardware and software through GitHub and Zenodo repositories. The €1,800 award supported the publication of an additional open-access protocol paper detailing the assembling and usage of this tracking system, furthering our commitment to open science and technology transfer.


Enhanced Power Point Tracking for High Hysteresis Perovskite Solar Cells with a Galvanostatic Approach

CLENAR Energy Innovation Award (November 2024) The Aragón Energy Cluster recognized the Institute of Nanociencia y Materiales de Aragón (INMA) for the BONIFACE project, a collaborative initiative with Gres Aragón (SAMCA Group). This project develops innovative photovoltaic technology integrated into building materials, specifically focusing on halide perovskite photovoltaic cells integrated into porcelain stoneware substrates.

SAMCA Award for Technological Development (January 2025) The most recent recognition came from the SAMCA Chair of Technological Development of Aragón, awarding its 5th Multidisciplinary Innovation Prize to the BONIFACE project. The jury highlighted its innovative approach in combining photovoltaic technology with traditional ceramic construction materials, emphasizing its potential for transforming both the ceramic industry and the sustainable construction sector.

Awards Ceremony (03-Apr-2025)

Catedra SAMCA Desarrollo tecnológico de Aragón

Video and pictures

Project Impact

The BONIFACE project represents a significant advancement in sustainable building technologies, combining environmental benefits with economic innovation. By integrating photovoltaic technology with traditional ceramic materials, the project simultaneously addresses energy efficiency and construction sustainability while creating new market opportunities. This approach not only revitalizes the Spanish ceramic industry but also positions Spain as a leader in building-integrated photovoltaic technology. The project’s comprehensive impact extends from reducing CO2 emissions to improving building energy efficiency, ultimately benefiting end-users through reduced energy costs and enhanced thermal comfort.

Future Directions

These recognitions reinforce our commitment to technology transfer and industrial application of research. The BONIFACE project (CPP2022-009766) exemplifies this approach, bridging academic research with industrial implementation through 2026. Similarly, our development of the Perovskino system demonstrates our dedication to creating practical, open-source solutions that can be readily adopted by the research community and industry partners. This focus on transferable technology and open innovation continues to guide our research strategy, ensuring our scientific advances have direct industrial applications.

Acknowledgments

Special thanks to our research team members and collaborators Marta Haro Remón, Roberto Casas, Arturo Sanz Marco, Alberto Lafuente and Cristina Momblona Rincón, as well as our institutional partners at INMA CSIC-University of Zaragoza and the SAMCA Group. These achievements would not be possible without their collaborative effort and support.

Listado de Referencias para el documento Visión

2024-07-10T16:35:10+00:00

Lewis, N. S. Toward cost-effective solar energy use. Science 315, 798-801, DOI (2007).
Kojima, A., Teshima, K., Shirai, Y. & Miyasaka, T. Organometal Halide Perovskites as Visible-Light Sensitizers for Photovoltaic Cells. J. Am. Chem. Soc. 131, 6050-6051, DOI (2009).
Park, N.-G., Grätzel, M., Miyasaka, T., Zhu, K. & Emery, K. Towards stable and commercially available perovskite solar cells. Nat. Energy 1, 16152 DOI (2016).
Best Research Cell Efficiencies NREL
Yu, H. J. J. & Geoffron, P. in Photovoltaic Solar Energy Conversion (eds Shiva Gorjian & Ashish Shukla) 413-437 (Academic Press, 2020).
Green, M. A. How Did Solar Cells Get So Cheap? Joule 3, 631-633, DOI (2019).
https://www.chemistryworld.com/news/first-building-integrated-deployment-shows-perovskite-solars-growing-maturity/3009953.article
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Juarez-Perez, E. J. & Haro, M. Perovskite solar cells take a step forward. Science 368, 1309-1309, DOI (2020).
Khenkin, M. V., Katz, E. A. & others. Consensus statement for stability assessment and reporting for perovskite photovoltaics based on ISOS procedures. Nature Energy 5, 35-49, DOI (2020).
Wang, S., Jiang, Y., Juarez-Perez, E. J., Ono, L. K. & Qi, Y. Accelerated degradation of methylammonium lead iodide perovskites induced by exposure to iodine vapour. Nat. Energy 2, 16195, DOI (2017).
Juarez-Perez, E. J., Hawash, Z., R. Raga, S., Ono, L. K. & Qi, Y. Thermal degradation of CH3NH3PbI3 perovskite into NH3 and CH3I gases observed by coupled thermogravimetry - mass spectrometry analysis. Energy Environ. Sci. 9, 3406-3410, DOI (2016).
Juarez-Perez, E. J. et al. Photodecomposition and thermal decomposition in methylammonium halide lead perovskites and inferred design principles to increase photovoltaic device stability. J. Mater. Chem. A 6, 9604-9612, DOI (2018).
Juarez-Perez, E. J., Ono, L. K. & Qi, Y. Thermal degradation of formamidinium based lead halide perovskites into sym-triazine and hydrogen cyanide observed by coupled thermogravimetry - mass spectrometry analysis. J. Mater. Chem. A 7, 16912-16919, DOI (2019).
Juarez-Perez, E. J., Ono, L. K., Uriarte, I., Cocinero, E. J. & Qi, Y. Degradation Mechanism and Relative Stability of Methylammonium Halide Based Perovskites Analyzed on the Basis of Acid-Base Theory. ACS Appl. Mater. Interfaces 11, 12586-12593, DOI (2019).
Juarez-Perez, E. J. Comment on “Probing the Origins of Photodegradation in OrganicInorganic Metal Halide Perovskites with Time-Resolved Mass Spectrometry”, Sustainable Energy & Fuels, 2018. Updated response (March 14, 2019) DOI (2019).
Islam, M. B., Yanagida, M., Shirai, Y., Nabetani, Y. & Miyano, K. Highly stable semi-transparent MAPbI3 perovskite solar cells with operational output for 4000 h. Sol. Energy Mater. Sol. Cells 195, 323-329, DOI (2019).
Bisquert, J. & Juarez-Perez, E. J. The Causes of Degradation of Perovskite Solar Cells. J. Phys. Chem. Lett. 10, 5889-5891, DOI (2019).
Grancini, G. et al. One-Year stable perovskite solar cells by 2D/3D interface engineering. Nat. Commun. 8, 15684 DOI (2017).
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Dunfield, S. P. et al. From Defects to Degradation: A Mechanistic Understanding of Degradation in Perovskite Solar Cell Devices and Modules. Adv. Energy Mater. 10, 1904054, DOI (2020).
Juarez-Perez, E. J., Momblona, C., Casas, R. & Haro, M. Enhanced Power Point Tracking for High Hysteresis Perovskite Solar Cells: A Galvanostatic Approach. arXiv, DOI (2023).
Juarez-Perez, E. J., Momblona, C., Casas, R. & Haro, M. Enhanced power-point tracking for high-hysteresis perovskite solar cells with a galvanostatic approach. Cell Reports Physical Science 5, 101885 DOI (2024).
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Ciria-Ramos, I., Juarez-Perez, E. J. & Haro, M. Solar Energy Storage Using a Cu2O-TiO2 Photocathode in a Lithium Battery. Small, 2301244, DOI (2023).
Ciria-Ramos, I. et al. Electrochemical Performance of M(dca)2pyz (M= Fe, Co, and Ni) MOFs as Sustainable Anodes in Lithium-Ion Batteries. J. Mater. Chem.A, DOI (2024).

The Perovskino

2024-01-30T08:35:10+00:00

Innovating Solar Cell Stability Assessment: The Perovskino Gizmo

In the realm of emerging solar photovoltaic technologies, assessing the operational stability of cells at the laboratory level presents a significant challenge. This challenge stems from the need for specialized equipment dedicated solely to this task over extended periods. Currently, to obtain representative data on the operational stability of a perovskite cell, continuous monitoring of its maximum power point is required for a time interval ranging from 500 to 1000 hours, as commonly reported (Figure 1).


Figure 1: T80 (hours) vs Publication date of stability tests on Perovskite Solar Cells. Source: 1. The Perovskite Databse Project; 2. Materials Zone; 3. An open-access database and analysis tool for perovskite solar cells based on the FAIR data principles (2022)

The evaluation process involves the exclusive use of at least one potentiostat and a solar simulator for each device under study. While a solar simulator can illuminate multiple devices simultaneously, each typically requires a potentiostat to apply voltage and measure current at the cell terminals to determine its maximum power.

This equipment limitation has resulted in very few laboratories worldwide specializing in emerging photovoltaic research having the appropriate resources to conduct a comprehensive analysis of cell stability across a sufficient number of cells. This difficulty hampers the attainment of statistically significant results supporting improvements in stability regarding design and/or composition of active layers.

In summary, much more exhaustive research is needed in the area of operational stability of these devices. However, conducting tests on multiple cells over extended periods, coupled with the expensive necessary equipment, poses a significant challenge to progress in this field.

Unlike the assessment of simple cell efficiency with a current-voltage (JV) curve, which can be done quickly, economically, and automatedly, measuring operational stability is inherently a slow and costly process due to the required standard equipment. Additionally, it is complicated due to the specific characteristics of perovskite cells that cannot be evaluated with conventional algorithms used in traditional photovoltaics, where JV curves do not exhibit hysteresis issues.

This context helps understand why, despite advances in efficiency, the field of operational stability in perovskite solar cells has not progressed at the same level. This aspect of operational stability is crucial for the commercial development of emerging perovskite-based photovoltaics.

The EASI project adopted an innovative approach to address this issue, the development of the “Perovskino” gizmo.

The “Perovskino” is a maximum power point tracker for photovoltaic cells designed with a maximum cost reduction approach. Their function will be crucial for effectively and economically tracking the performance of perovskite photovoltaic cells over a long period.

The Low-Cost MPP Tracker “Perovskino”

“Perovskino” is a low-cost hardware (less than 5€ per unit) for long-term operational stability measurements in perovskite solar cells. Our research focuses on developing an innovative hardware solution for research purposes that allows a high number of simultaneous long-term stability measurements, eliminating the need for expensive and complex monitoring systems. Our hardware design is based on the Arduino platform, and specifically, our development is a shield that attaches to these Arduino UNO R3 Boards (Figure 2).


Figure 2: The Perovskino

Due to the peculiarity of galvanostatically measuring cell efficiency, along with the pronounced hysteresis exhibited by perovskite devices, the “Perovskino” features a novel maximum power point tracking (MPPT) algorithm, the firmware of which we have deposited in the GitHub repository. Our galvanostatic MPPT algorithm ensures continuous and accurate tracking of cells with hysteresis. All work related to the development of this device and its code has been deposited as a preprint on arXiv Enhanced Power Point Tracking for High Hysteresis Perovskite Solar Cells: A Galvanostatic Approach and submitted to a peer-reviewed journal.

Stay tuned for updates on the groundbreaking innovations from the Perovskino gizmo, as we strive to revolutionize the assessment of operational stability in perovskite solar cells and drive forward the commercialization of this promising technology.

Partner offer for M-ERA.NET

2022-03-28T13:59:10+00:00

My partner offer to participate in the M-ERA.NET 2022 was published here.

Competences / Expertise

ARAID researcher at Instituto de Nanociencia y Materiales de Aragón (INMA) CSIC-Universidad de Zaragoza and a member of the Nanostructured Films & Particles Research Group adscribed to the Nanomaterials for Solar Energy Harvesting research line.

Versatile scientist with a multidisciplinary background in Materials Science with 12+ years of experience providing PhD-level scientific services to multiple research projects conducted in academia and industry. Methodical and solutions-oriented scientist with 60+ publications in high impact peer reviewed journals and 50+ conferences. Stanford Ranking top 2% scientist for single year (2020). Extensive experience in fabrication and characterization of hybrid perovskite based optoelectronic devices (perovskite solar cells).

Technology, services and methodologies offered:

Synthesis of materials: Fume-hoods, stoves, autoclaves and ovens, calcination under different atmospheres, centrifuges, Schlenk line, microwave assisted synthesis equipment, micro-fluidics systems.

Thin film deposition: Dip coater, spin coater, microdispensing equipment, glove box. Nanomaterials and thin film characterization: TGA, DLS, MP-AES, UV-VIS-NIR spectrometry (with integrating sphere), Nitrogen adsorption equipment ASAP 2020 and TRISTAR, Raman, FTIR, TEM, SEM, XRD, UPS, XPS, AFM, PLD, MBE, PECVD, sputtering, clean room facilities.

Solar cell characterization: Three solar simulators, LED, halogen and Xenon Lamps. Electronics for J-V curves and MPP tests. EQE system detecting up to 1600 nm with Ge detector.

Relevant running projects as PI:

PID2019-107893RB-I00. Perovskite-nanocrystal heterojunction solar cells with Extended AbSorption and Improved performance - EASI https://easi.unizar.es/ and Other projects

Contact

Dr Emilio J. Juarez-Perez at ejjuarezperez(a)unizar.es

Organisation: Instituto de Nanociencia y Materiales de Aragón (INMA) CSIC-Universidad de Zaragoza

Organisation Type / Partner Type: Research Organization

Country: Spain

Website: https://inma.unizar-csic.es/

Links para artículos en Google Académico (actualizado)

2021-09-11T08:35:10+00:00

13 Apr 2022. Post actualizado, ver más abajo

Google Académico ahora indica qué artículos están disponibles en acceso público dependiendo del tipo de financiación que recibió la investigación.


Artículos en mi ficha de Google Académico de artículos disponibles y no disponibles en septiembre de 2021

Si se desea hacer una correción, las opciones disponibles son un poco menos que surrealistas (ninguna me vale):


Opciones disponibles para hacer una corrección

Tampoco tengo los drafts antes del formateado de la revista y si los tengo desconozco si en ese momento corresponden exactamente a la versión final publicada y si tengo derecho a subir el manuscrito de esta forma aunque no tenga el formato final que le dio la revista.

La solución que he encontrado es crear un pdf de una sola página con los datos de la referencia y el abstract copiado verbatim. Entonces indico mi email para que me soliciten el artículo.

Sin embargo parece que hay problemas para subir el fichero.


Hay algún problema para subir el fichero

Mientras esperamos que arreglen esto, usaré este post para listar los links a esos pdfs.

2022-04-13. Actualización.

La idea ha funcionado parcialmente. 6 de 10 artículos han sido encontrados por el robot de google.


PDF encontrado en los links de este post

Pero cuatro de ellos todavía no. Ahora se comprueba que la subida manual a drive ha sido arreglada y se pueden subir los pdfs. Los cuatro restantes que no habían sido capturados los subo por este método:


PDFs subidos a google drive

Y finalmente ya no me quedan artículos no accesibles.


Public access

Home made efficient tandem coupling of TG/DTA and MS equipment

2020-07-18T08:35:10+00:00

In principle, the coupling of these two units is straightforward, a portion of the exhaust gas from the TG/DTA unit is diverted for sampling in the MS quadrupole unit for subsequent m/z analysis.

Depending on the TG/DTA model, it may be possible to find a specific commercial accessory to make this connection between both units. However, this accessory is not always available for a specific TG/DTA model. Usually, this accessory is designed for TG/DTA equipment including a horizontal type furnace or hot chamber with no moving parts attached to this part of the equipment. In this case, the differential thermal balance TG-DTA2000SE (Sirius) from Netzsch is a moving vertical electric furnace that uses a retractable head that allows access to the sample location for measurement analysis. The exhaust is located on the top of this moving head that covers the sample stage.


The differential thermal balance TG-DTA2000SE (Sirius) by Netzsch

There is no coupling accessory for this equipment in order to take in-line samples for the MS quadrupole. Then, a T-shaped connector can be placed in the exhaust output and feed the MS device directly. However, by doing that, there is a remarkable delay between the maximum observed peak of the DTG trace (derivative of the TG trace or mass flow) and the total/partial pressure detected by the MS equipment. The thermal degradation of the standard calcium oxalate material shows especially a large delay of 84 seconds for the peak related to the water portion release.


TG and calculated DTG traces from the TG/DTA equipment and partial pressure measured in the MS equipment. During the test, a 100 ml/min inert gas was used as carrier gas flow.

Despite sampling being done as close as possible to the exhaust of the TG/DTA equipment, this delay could be alleviated if sampling could be done internally close to the sample stage by using a metallic capillar. In this way, the gas volumetric flow for sampling would be instantaneous equal inside the TG/DTA and the fused glass silica capillar from the MS equipment. The scheme below depicts the conventional attachment and the capillar based sampling procedure.


(Left) conventional sampling from T-shaped connector and (right) sampling using inner capillar close to the sample stage. Red and green arrows denotes fast and slow flow, respectively

After that, the problem becomes how to hold this concentric capillar inside the main exhaust line considering that the oven head of TG-DTA2000SE is a mobile part. It could be problematic because the capillar input is placed just 1/2 cm above the sample boats and, therefore, a tight holding between the accessory and system is necessary. The tight holding was solved by designing a helmet for the oven head where external piping, valve and concentric capillar are attached and moving solidary to the oven-head.


Helmet holding exhaust and capilar lines in the head of the movable oven

The improvement minimizing the delay upon calcium oxalate gas releaseases measured in both equipment is remarkably good compared to the conventional sampling strategy.


TG and calculated DTG traces from the TG/DTA equipment and partial pressure measured in the MS equipment using inner capillar for the connection of both equipment.

A blueprint for the helmet design can be downloaded here.

This TG/DTA helmet accesory was used recently for detecting released gas compounds from hybrid halide perovskite.¹^, ² Please cite one of these articles if you find useful the blueprint of the helmet for coupling your devices.

Juarez-Perez, E.J., Ono, L.K., Maeda, M., Jiang, Y., Hawash, Z. and Qi, Y. Photodecomposition and thermal decomposition in methylammonium halide lead perovskites and inferred design principles to increase photovoltaic device stability 2018 J. Mater. Chem. A Vol. 6, pp. 9604-9612 ↩
Juarez-Perez, E.J.,* Ono, L.K. and Qi, Y. Thermal degradation of formamidinium based lead halide perovskites into sym-triazine and hydrogen cyanide observed by coupled thermogravimetry - mass spectrometry analysis 2019 J. Mater. Chem. A Vol. 7, pp. 16912-16919 ↩

HCN decomposition gas release of formamidinium based perovskite

2020-06-20T08:35:10+00:00

Invited Talk: What does the HCN decomposition gas release tell us about the stability of formamidinium based perovskite?

An invitated presentation for the “Methods to analyze stability of perovskite-type absorbers and solar cells” session in the online NANOGE (StabPero nanoGe) meetings (02/06/2020).


First slide cover

This presentation was deposited in Zenodo with DOI:10.5281/zenodo.3871939

Hybrid lead halide DMAPbX₃ hexagonal perovskites

2020-01-15T08:35:10+00:00

Article: Hybrid lead halide [(CH₃)₂NH₂]PbX₃ (X = Cl^- and Br^-) hexagonal perovskites with multiple functional properties


Hybrid lead halide DMAPbX₃hexagonal perovskites with multiple functional properties

We have been able to prepare two new lead halides with the formula DMAPbX₃ (where DMA is dimethylammonium and X is Cl^- and Br^-), which display a 4H-hexagonal perovskite polytype, an unusual crystal structure in hybrid organic–inorganic perovskites. Both compounds experience a first-order phase transition, the chloride at ∼320 K and the bromide at ∼250 K, which involves two cooperative processes: an off-center shift of the lead cations and an order-disorder process of the DMA cations. Additionally, a sharp dielectric transition is associated with this structural transition in both hybrids. Both compounds are semiconductors with band gap values of 3.5 eV (X: Cl^- ) and 3.0 eV (X: Br^-). Also, the LT-phase of the Br^- compound displays a broad red light photoluminescence (PL) emission (620 nm) and PLE excitation with the maximum at a soft UV wavelength (360 nm). This broadband emission and large Stokes-shifted PL seem to be related to a self-trapped exciton mechanism. Therefore, the uncommon 4H-hexagonal perovskite is a promising crystal structure for understanding and designing new hybrid materials with broad photoluminescent emission and dielectric properties.

The pseudopotentials used with the Siesta program can be downloaded here.

LATEX - plantilla para CV de una página

2019-07-19T11:59:00+00:00

Una plantilla en L^AT_EX para preparar un CV de una sola página o CV “20 segundos”.


Screenshot del CV generado

Puedes descargar la plantilla desde aquí.

Un CV (pdf) generado con esta plantilla se muestra aquí.

Esta plantilla ha sido adaptada de TwentySecondsCurriculumVitae-LaTex

Round Robin Test Project

2018-09-18T09:57:27+00:00

Article: Benchmarking Chemical Stability of Arbitrarily Mixed 3D Hybrid Halide Perovskites for Solar Cell Applications

Accurate and fast assessment of the intrinsic instability of mixed composition hybrid halide perovskite material is of vital importance for the development of perovskite solar cells. A longer lifetime close to current silicon based technology is a mandatory property for perovskite solar cells to reach commercial applications. The conventional method to evaluate the operational stability performance of perovskite solar cells relies on tracking maximum power efficiency on devices. However, this operational stability testing procedure requires a long measurement time, which is an inefficient procedure to screen the huge compositional space of mixed perovskites. Here, a thermal degradation protocol is shown for fast preliminary screening evaluation of the stability of any mixed 3D hybrid perovskite material. This stability assessment determines two independent parameters for stability quantification:

1. Degradation temperature (T_d)

2. Heat absorbed during degradation (Q_HAMDR)


Summary of the stability map of selected compositions of hybrid perovskite

An experimental entropic-like parameter can be derived addressing the relative stability for each mixed hybrid perovskite composition. In addition, a first principles theoretical approach (DFT) is described for the in silico search of optimal mixed composition perovskites. This experimental stability benchmarking protocol is able to signify several general rules of thumb to find enhanced stability trends in mixed composition perovskites prior to device assembly and conventional stability tests.

Round Robin Test Project

I am running a long term Round-Robin test to verify the inter-laboratory reproducibility (accuracy and precision) of this stability benchmarking protocol consisting of a controlled thermal degradation of perovskite material to obtain these two empirical figures of merit for stability quantification.

The equipment necessary to participate in this Round Robin Test is a Thermogravimetry/Differential Thermal Analyzer (TG-DTA) able to run the measurement under inert gas conditions (preferably He but N₂ could work too), alumina crucibles for the sample measurement, an agate mortar and pestle set, powder X-ray facility to check material purity and the reagents and solvents needed to synthesize hybrid perovskite (CsI, CsBr, MAI, MABr, FAI, FABr, PbI₂ and PbBr₂).


Scheme depicting the measurement of TG and DTA for hybrid perovskite material under a constant heating ramp

Goals

Amenable goal: To consolidate FAPbBr₃ as de facto standard to compare qualitatively the stability between mixed perovskites using only T_d as the straightforward figure of merit of the method.

Ambitious goal: A two-sigma level on accuracy/precision in two figures of merit evaluated at intralaboratory level is obtained and this relatively easy measurement can be consolidated as a standard protocol for pre-screening general stability of hybrid perovskites before conventional stability tests carried out in working devices.

Major Hints/Notes

We note that sample preparation is a key to obtain reproducible results and probably the method is equipment dependent. Please, check carefully section 3.3 in this Supporting Information File.
This study as announced is tentative in nature and major changes may be made in the final goals according to suggestions from potential collaborators.
Tentatively, pristine chemical compositions such as MAPbI₃, MAPbBr₃, FAPbI₃ and FAPbBr₃ would be analyzed but other compositions and conditions could be agreed depending on the number of participants.
The output of this study would be a publication in due time authored by all collaborators.
Updates related to this project will be done in this post.
Please contact me if you are interested in participating in this Round Robin inter-laboratory test with your TG-DTA equipment, if you need more information, inquiries or just want to make suggestions.


Two figure of merit defining stability of arbitrary composition hybrid perovskite

2019-05-01. UPDATE: a new TG-DTA equipment with horizontal tube furnace has been added to the equipments pool. A new set of benchmarking measurements is in progress.

Photo-,thermal-decomposition in methyalammonium based perovskite

2018-06-12T16:42:33+00:00

Article: Photodecomposition and thermal decomposition in methylammonium halide lead perovskites and inferred design principles to increase photovoltaic device stability

Hybrid lead halide perovskites have emerged as promising active materials for photovoltaic cells. Although superb efficiencies have been achieved, it is widely recognized that long-term stability is a key challenge intimately determining the future development of perovskite-based photovoltaic technology. Herein, we present reversible and irreversible photodecomposition reactions of methylammonium lead iodide (MAPbI₃). Simulated sunlight irradiation and temperature (40-80 ºC) corresponding to solar cell working conditions lead to three degradation pathways: (1) CH₃NH₂+ HI (identified as the reversible path), (2) NH₃+ CH₃I (the irreversible or detrimental path), and (3) a reversible Pb⁽⁰⁾ + I₂(g) photodecomposition reaction. If only the reversible reactions and take place and reaction can be avoided, encapsulated MAPbI₃can be regenerated during the off-illumination timeframe. Therefore, to further improve operational stability in hybrid perovskite solar cells, detailed understanding of how to mitigate photodegradation and thermal degradation processes is necessary. First, encapsulation of the device is necessary not only to avoid contact of the perovskite with ambient air, but also to prevent leakage of volatile products released from the perovskite. Second, careful selection of the organic cations in the compositional formula of the perovskite is necessary to avoid irreversible reactions. Third, selective contacts must be as chemically inert as possible toward the volatile released products. Finally, hybrid halide perovskite materials are speculated to undergo a dynamic formation and decomposition process; this can gradually decrease the crystalline grain size of the perovskite with time; therefore, efforts to deposit highly crystalline perovskites with large crystal sizes may fail to increase the long-term stability of photovoltaic devices.


Scheme depicting several routes (reversible and irreversible) for MAPbI₃ decomposition under temperature and lightning factors


Parylene/Gold cathode “bubbling” on top of a biased perovskite thin film releasing gases. The perovksite fringe between electrodes is ~100 micrometers width. 200V/100um is an electric field similar to suffered by 1 um thick perovskite layer on solar cells

Word on ARM tablet

2017-12-28T19:13:39+00:00

Word on ARM tablet

At first sight there is nothing special in the picture, a netbook running MS Word. A more close view and one can observe that the word processor is really appearing inside one Chrome tab. In fact, it is really a tab in Chrome OS running on one Asus Chromebook C100 Flip. It is an inexpensive chromebook mounting an ARM type processor including ~9 hours of battery life. How is it done if at the moment neither wine or virtualbox programs have a stable ARM version?


A client-server scheme showing the software layers needed to run MS Word in this C100 chromebook

The trick is that the chromebook is running crouton behind the scene. This crouton (a Debian chroot in my case) is running a rdp “ssheathed” connection managed by Remmina to a headless virtualbox machine server running the Word of a W7. LAN connections are ok and fluid but WAN connections could be tricky. In this case of slow connections, I prefer running directly x11vnc (also managed by Remmina). There are few program utilities not runnning in ARM processors still there and needing this kind of nested/layered connections.

Now shipping - Hybrid perovskite solar cells

2017-09-29T02:19:29+00:00

Now shipping:

Hybrid Perovskite Solar Cells: the Genesis and Early Developments 2009-2014.

pre-order here

Progress on Novel Perovskite Materials and Solar Cells

2017-07-08T12:03:41+00:00

Article: Progress on Novel Perovskite Materials and Solar Cells with Mixed Cations and Halide Anions

Hybrid halide perovskite materials have been studied intensively for photovoltaic applications. Major concerns for the commercialization of perovskite photovoltaic technology to take off include long-term stability and optimal band-gap. Molecular composition engineering has been proposed to address the above concerns. Among the best six certified power conversion efficiencies reported by National Renewable Energy Laboratory (NREL) on perovskite-based solar cells, four are based on mixed perovskites. In this article, we review the recent progress on the synthesis and fundamental aspects of mixed cation and halide perovskites correlating with device performance and long-term stability.


playing the Perovskite Pachinko

Carborane-stilbene dyads on photoluminescence properties

2017-03-03T16:14:38+00:00

Article Carborane–stilbene dyads: the influence of substituents and cluster isomers on photoluminescence properties

Two novel styrene-containing meta-carborane derivatives substituted at the second carbon cluster atom (Cc) with either a methyl (Me) or a phenyl (Ph) group are introduced herein along with a new set of stilbene-containing ortho- (o-) and meta- (m-) carborane dyads. The latter set of compounds have been prepared from styrene-containing carborane derivatives via a Heck coupling reaction. All compounds have been fully characterised and the crystal structures of seven of them were analysed by X-ray diffraction. The absorption spectra of these compounds are similar to those of their respective fluorophore groups (styrene or stilbene), showing a very small influence of the substituent (Me or Ph) linked to the second Cc atom or the cluster isomer (o- or m-). On the other hand, fluorescence spectroscopy revealed high emission intensities for Me-o-carborane derivatives, whereas their Ph-o-carborane analogues evidenced an almost total lack of fluorescence, confirming the significant role of the substituent bound to the adjacent Cc in o-carboranes. In contrast, all the m-carborane derivatives display similar photoluminescence (PL) behavior regardless of the substituent attached to the second Cc, demonstrating its small influence on emission properties.

DFT calculations were performed to successfully complement the photoluminescence studies, supporting the experimentally observed photophysical behavior of the styrene and stilbene-containing carborane derivatives. In conclusion, in this work it is proved that it is possible to tailor the PL properties of carborane-stilbene dyads by changing the Cc substituent and the carborane isomer.


DOS and HOMO-LUMO orbitals for the stilbene-carborane derivatives. If LUMO is located in phenyl moiety, the PL of the compound is deactivated


Front cover for the issue. Dalton Trans., 2017,46, 2033-2033

Thermal degradation of CH₃NH₃PbI₃ perovskite into NH₃ and CH₃I gases

2016-12-29T16:25:42+00:00

Article: Thermal degradation of CH₃NH₃PbI₃ perovskite into NH₃ and CH₃I gases observed by coupled thermogravimetry mass spectrometry analysis

Thermal gravimetric and differential thermal analysis (TG-DTA) coupled with quadrupole mass spectrometry (MS) instrumentation and first principles calculations were employed to elucidate the chemical nature of released gases during the thermal decomposition of MAPbI₃. Contrarily to the common wisdom that CH₃NH₃PbI₃ is decomposed into CH₃NH₂ and HI, the major gases were methyliodide (CH₃I) and ammonia (NH₃). We anticipate our finding will provide new insights for further formulations of the perovskite active material and device design that can prevent the methylammonium decomposition and thus increase the long-term stability of perovsktie-based optoelectronic devices.

This article called the attention of the specialized media: Altmetrics


Graphical Abstract figure for the TOC


Figure used in the Back cover of the issue. Program: Blender

Two energy pathways for methylammonium iodide decomposition depending of released products


Energy consuming reaction for decompostion into CH₃NH₂ and HI


Energy releasing reaction for decompostion into methyliodide (CH₃I) and ammonia (NH₃)

SOFT - Effect of mesostructured layer on PSC

2015-12-29T09:00:28+00:00

Effect of Mesostructured Layer upon Crystalline Properties and Device Performance on Perovskite Solar Cells

One of the most fascinating characteristics of perovskite solar cells (PSCs) is the retrieved obtainment of outstanding photovoltaic (PV) performances withstanding important device configuration variations.Here we have analyzed hybrid perovskite material in planar or in mesostructured (MS) configurations, employing both titania and alumina scaffolds, fully infiltrated with perovskite material or presenting an overstanding layer.


Experimental TRPL fluorescence decays on PSC layers

Model fitting decays were obtained using TRPL-PVK

SOFT - a 3 level scale view of the graphite electrode

2015-12-27T09:00:18+00:00

A 3 level scale view of the graphite electrode in Li-ion battery. Graphene sheets “sculpted” using Pymol, rendering using AOI.

SOFT - blankets for devices

2015-12-25T09:00:37+00:00

AOI renders of device covered by texture layers.



AOI - Art of Illusion generated figures using plastic and fabric textures for the blankets

Recombination reduction on lead halide perovskite solar cells

2015-12-22T18:03:46+00:00

Recombination reduction on lead halide perovskite solar cells based on low temperature synthesized hierarchical TiO₂ nanorods

Intensive research on the electron transport material (ETM) has been pursued to improve the efficiency of perovskite solar cells (PSCs) and decrease their cost. More importantly, the role of the ETM layer is not yet fully understood, and research on new device architectures is still needed. Here, we report the use of three-dimensional (3D) TiO₂ with a hierarchical architecture based on rutile nanorods (NR) as photoanode material for PSCs.


Recombination reduction on lead halide perovskite solar cells

SOFT - Fullerene vacuole

2015-12-22T17:54:59+00:00

Fullerene Vacuole.

This sketch seeks to represent the P3HT / PCBM blend in a working organic solar cell.

All PCBM and P3HT “molecules” were imported to AOI from conventional X-ray quality .xyz files using meshconv 3D mesh converter, version 0.83 (by Patrick Min).


P3HT/PCBM blend

Polymer/Perovskite Amplifying Waveguides for Active Hybrid Silicon Photonics

2015-09-23T09:19:51+00:00

Polymer/Perovskite Amplifying Waveguides for Active Hybrid Silicon Photonics

The emission properties of hybrid halide perovskites are exploited to implement a stable and very low power operation waveguide optical amplifier integrated in a silicon platform.


Polymer/Perovskite Amplifying Waveguides for Active Hybrid Silicon Photonics

This novel photonic device is assembled depositing a layer of hybrid halide perovskite and poly(methyl methacrylate) (PMMA) on SiO₂/Si wafer substrate. The PMMA polymer layer simultaneously develops two fundamental roles in the device, first allowing to propagate the pump and signal beams along suitable long distances and secondly protecting the hybrid perovskite layer from moisture/air degradation.

The device presents a net gain of around 10 dB cm^-1 and 3-4 nm linewidth with an energy threshold as low as 2 nJ pulse^-1. A decreased threshold compared to previous results which was remarkably obtained without requiring short pulsed lasers, a clear indicator of the powerful waveguide approach proposed in the present work.

Bibtex - Database on Hybrid Halide Perovskite optoelectronics and related topics.

2015-09-21T06:44:17+00:00

A database containing almost 1340 entries on the topic of hybrid halide perovskite optoelectronics. Papers, reviews and related documents fetched via Scopus and Google Scholar. Updated in a monthly basis.

* Availabe in bibtex and endnote file format. The database does not contain pdfs but they could be easily fetched using JabRef (see red arrow in the figure).


Red arrow indicates google scholar html link

update 08/10/18: 8096 entries.

A sunny afternoon in Castellón

2015-05-01T22:51:24+00:00

Yellow Is the New Black

2015-04-22T09:21:14+00:00



Yellow Is the New Black

we meet again at the light bulb

2015-04-19T19:46:41+00:00


we meet again at the light bulb.

The animation/render was prepared enterily using Art of Illusion (AOI).

A Prolific Year

2015-04-19T18:21:08+00:00

We have been highlighted in an editorial from The Journal of Physical Chemistry Letters “A Prolific First Five Years” because our paper “Role of the Selective Contacts in the Performance of Lead Halide Perovskite Solar Cells” was the second most cited paper during 2014.

SOFT - Behind the scene

2015-04-03T16:50:18+00:00


nanotube/TiO₂ nanocomposite battery anodes

This graphical abstract for the TOC of this article was built up using almost exclusively the program Art of Illusion(AOI). Art of Illusion is a free, open source 3D modeling and rendering studio which is very suitable for this kind of artwork and also it is easy to learn.

The main idea for the picture including the nanocomposite required the inclusion of a multi-walled carbon nanotube. A first approach could be to import the atomic coordinates of the nanotube from a third party program and try to render the composite. However, there was a more complication because such nanotube should be cut along the axial axis to show the electron paths. Also, it was not easy to find the .xyz atomic coordinates of such multiwalled nanotube. Then, we decided another approach instead of crude atom-by-atom insertion of the nanotube inside the scene. As you can see in the detailed figure (bottom panel), the nanotube is really a cylinder sculpted using the boolean tool of AOI where a picture of overlapping layers of graphene has been mapped within its surface. The trick is that choosing the adequated point of view of the AOI camera, this detail become unnoticed behind of the scene.

SOFT - The cover of thesis that never came to be (or too many chemicals here)

2015-04-03T16:25:37+00:00

Some time ago a coworker asked me to design the cover for his PhD thesis. After he explained to me about that was the thing, I could more or less understand that dangerous organochlorine compounds entered from one side and the magical zeolite destroys them to generate harmless CO₂ and HCl spat from the other side.

I thought of composing a figure with all the chemicals that he had mentioned to me. And clearly to draw the zeolite would be a problem. By that time I was rendering all using povray.


The discarded cover

The procedure I followed to compose the above figure was:

I took a cif file of a zeolite from the Crystallography Open Database and expanded the structure up to the desired size with Mercury. Then I saved such crystal portion as a .xyz file type.
The saved file was open using G abedit and there the other molecules are added from the library. It seems that carbonaceous based deposition happens within the zeolite pores, this is shown as plain huge on purpose carbon atoms.
The full set was saved as xyz file type again (it is also possible as pdb filetype) and it was open in P y MOL. The zeolite is shown in “sticks” mode, the gas phase molecules as “balls and sticks” mode molecules and the carbon residue as spheres with increased diameter size. The image rendering was also made using PyMOL.
The final figure is composed using GIMP where a fancy brush of chalk arrows was used indicating the chemical reaction direction.

Later my colleague told me that on the upper floor had not liked the cover. Too many chemical compounds in the figure. He ended up placing a photograph with a swarm of pipelines as the cover because in fact it was a Chemical Engineering PhD thesis. But I learned the versatility of PyMOL to compose and render images.

Perovskites on plastic!

2013-12-04T00:58:42+00:00

Recently, solar cells devices based on halide perovskite using a flexible substrate have jumped on the scene. These exciting results have been obtained independently by two different groups. The first paper become from the Energy Research Institute of Singapore. There, they have used ZnO nanorods as scaffold for the MAPbI₃ perovskite and they have achieved a conversion effiency of 2.62% on a PET-based substrate[1]. On the other side of the planet, from the Clarendon Laboratory of the University of Oxford, a MAPbI_3-xCl_x cell have been assembled using also PET-based substrate[2]. In this case, the researchers have opted to build the unusual inverted stack placing the p-contact on the conductive substrate. Inverted stack is much harder to harmonize because the perovskite layer is particulary sensitive to any polar solvent used to deposit the following layers like the electron selective layer TiO_x, or hole blocking layer like bathocuproine[3]. Anyway, a 6% of efficiency on plastic substrate are good news for these promising photovoltaic active materials.
What is the next? Would there be a tandem cell for the end of 2013?

How do you prepare a 10 mg L^-1 solution of NaCl in water?

2013-09-28T00:29:12+00:00

You probably put 10 mg of common salt inside of one liter volumetric flask and poor water until the etched ring graduation mark is reached ensuring that there is not trace of the crystaline solid inside the flask. In this way you have prepared nicely one liter of a precise 10 mg L^-1 NaCl solution. In this way we were teached to prepare in a standard way our solutions reported using molarity units.

Lately, in the rush of the daily days, you could probably catch me taking 1 L of water and spreading a fast weighted spoon with 10 mg of salt to prepare the same not-so-accurate solution than above. Or maybe not, it depends obviously of the accuracy required later by the experiment.

But now you imagine that you need to prepare 1 mL of a 467 mg mL^-1 solution of PbI₂ in DMF. On other words, the famous 1 M solution of PbI₂ in DMF. Do you weigh the quantity of PbI₂ and follow a similar procedure as first described above filling with solvent a volumetric flask up to its mark on the glass? or, do you pour 1 mL of DMF solvent on 467 mg of PbI₂?

The IUPAC Gold Book established clearly the definition of amount concentration: molarity takes in consideration the mixture volume not the volume of solvent poured. In my hands, the former correct procedure using graduated volumetric flasks gives a ~ 42% w/w PbI₂ DMF suspension assuming that later or sooner the PbI₂ dust particles will dissolve without a significant volume change of the mixture. On the other hand, the “fast” and “wrong” method gets really a 33.1% w/w of PbI₂ in DMF as the amount concentration. It is a huge difference, 42 vs 33%, on reporting experimental procedures for solution preparation. In fact, the source of this mess is that for highly diluted concentrations, as the example entliting this post, the mismatch is negligible. Instead, these highly concentrated solutions labelled wrongly as 1 M will lead a significant error for others because researchers with standard education in Chemistry would be aware that “solution” volume could be a different quantity that “solvent” volume.

Noterworthy, this problem could be easily avoided reporting these high concentrated solutions using the most appropiated solute/solvent % w/w units instead of molarity units.

20/09/20018. Update: Be aware, after almost five years of writing this post entry, take it for granted: if you read the experimental section of an article on the topic of hybrid perovskite that they labeled as 1 M their solutions, they actually almost very probably poured X milliliters of solvent into X mmols of solute.

Perovskite solar cells: the dual way

2013-09-16T23:10:40+00:00

Perovskite solar cells: the dual way

This entry was written by JB and Emilio J. Juárez Pérez It has been 4 years since Tom Miyasaka and collaborators first reported the use of halide perovskites as a light harvester material in hybrid…

El Tobazo Canfranc

2013-08-15T00:07:44+00:00


Ladrillos de plomo rodeados por dewars


Otro experimento: ladrillos de plomo sobre ladrillos de Teflón

El Tobazo
http://www.lsc-canfranc.es

Spin casting PbI₂ on substrate

2013-07-08T12:21:13+00:00


PbI₂ on substrate ready for the two step hybrid perovskite deposition method

There's plenty of room at the bottom...

2013-07-03T16:26:46+00:00


…of the cupboard

A microwave-based method for the synthesis of carbon xerogel spheres

2012-05-28T11:05:46+00:00


Seven steps to obtain millimiter size carbon xerogel spheres

A microwave-based method for the synthesis of carbon xerogel spheres

Carbon xerogel spheres with millimeter-scale diameters were synthesized by a simple process using microwave radiation as the heating source. Using this type of heating it is possible to establish the gelation point of different resorcinol–formaldehyde solutions and stop the gelation step of the material at the exact time of gelation. Organic gel spheres can then be directly obtained by stirring in a silicone bath at 80 °C. Finally, carbonization is performed to obtain carbon xerogels with a spherical shape. The size and porous texture of the spheres can be controlled by adjusting the synthesis conditions.

Polyanionic Aryl Ether Cobaltabisdicarbollide Based Metallodendrimers

2012-04-26T15:29:00+00:00

Polyanionic Aryl Ether Metallodendrimers Based on Cobaltabisdicarbollide Derivatives. Photoluminescent Properties

Fluorescent Fréchet-type poly(aryl ether) dendrimers incorporating the 1,3,5-triphenylbenzene as core molecule and 3, 6, 9, or 12 terminal allyl ether groups have been prepared in very good yield by following the Fréchet convergent approach. Regiospecific hydrosylilation reactions on the allyl ether functions with the cobaltabisdicarbollide derivative Cs[1,1′-μ-SiMeH-3,3′-Co(1,2-C₂B₉H₁₀)₂] lead to different generations of Fréchet-type polyanionic metallodendrimers decorated with 3, 6, and 9 cobaltabisdicarbollide units.


Polyanionic Aryl Ether Cobaltabisdicarbollide Based Metallodendrimer

Grafting of metallacarboranes onto self assembled monolayers

2012-04-25T18:08:50+00:00

Grafting of Metallacarboranes onto Self-Assembled Monolayers Deposited on Silicon Wafers

Amine-, oxyamine-, and isocyanate-terminated self-assembled monolayers were deposited on silicon wafers for reaction with cobaltabisdicarbollide derivatives. The reaction of the isocyanate group with [NMe₄][8-NH₂-C₄H₈O₂-3,3-Co(1,2-C₂B₉H₁₀)(1,2-C₂B₉H₁₁)] gave homogeneous monolayers of cobaltabisdicarbollide moieties covalently linked to the surface.


Grafting of metallacarboranes onto self assembled monolayers

Rotamer Configuration in Metallabis(dicarbollide)

2012-04-24T15:34:00+00:00

The Role of C-H···H-B Interactions in Establishing Rotamer Configurations in Metallabis(dicarbollide) Systems

The rotamer controversy between the solid state cisoid and the gas phase calculated transoid in [3,3′-Co-(1,2-C₂B₉H₁₁)₂]^– has led to conclude that the anionic environment is crucial to determine the rotamer conformation and crystal packing in metallacarboranes. QTAIM has been applied to study intermolecular H ··· H short contacts that define the preferred rotamer. Its relation to the electron configuration of the transition metal is also studied.


Electrostatic potential mapping in cobalta-bis-dicarballide anion

Precise determination of the point of sol-gel transition in carbon gel synthesis

2012-04-23T15:37:00+00:00

Precise determination of the point of sol-gel transition in carbon gel synthesis using a microwave heating method

A simple and precise method for determining the point of gelation in microwave-assisted synthesis of organic gels is reported. This method provide a relevant information in the carbon gels field, as it can be applied to stop the gelation process at the precise instant for using the material in further processes where it is necessary to have the material with a specific viscosity (i.e., point of gelation).


Transition from sol to gel

Fluorescence of Styrene-containing carborane derivatives

2012-04-22T20:09:24+00:00

Synthesis and Characterization of New Fluorescent Styrene-Containing Carborane Derivatives: The Singular Quenching Role of a Phenyl Substituent

A set of neutral and anionic carborane derivatives in which the styrenyl fragment is introduced as a fluorophore group has been successfully synthesized and characterized. The reaction of the monolithium salts of 1-Ph-1,2-C₂B₁₀H₁₁, 1-Me-1,2-C₂B₁₀H₁₁ and 1,2-C₂B₁₀H₁₁ with one equivalent of 4-vinylbenzyl chloride leads to the formation of compounds 1-3, whereas the reaction of the dilithium salt of 1,2-C₂B₁₀H₁₂ with two equivalents of 4-vinylbenzyl chloride gives disubstituted compound 4. The closo clusters were degraded using the classical method, KOH in EtOH, to afford the corresponding nido species, which were isolated as tetramethylammonium salts. The crystal structure of the four closo compounds 1-4 were analyzed by X-ray diffraction. All compounds, except 1, display emission properties, with quantum yields dependent on the nature of the cluster (closo or nido) and the substituent on the second C_cluster atom. In general, closo compounds 2-4 exhibit high fluorescence emission, whereas the presence of a nido cluster produces a decrease of the emission intensity. The presence of a phenyl group bonded to the C_cluster results in an excellent electron-acceptor unit that produces a quenching of the fluorescence. DFT calculations have confirmed the charge-separation state in 1 to explain the quenching of the fluorescence and the key role of the carboranyl fragment in this luminescent process.


Fluorescence of Styrene-containing carborane derivatives

Decorating Poly(alkyl aryl-ether) Dendrimers with Metallacarboranes

2012-04-21T15:42:31+00:00

Decorating Poly(alkyl aryl-ether) Dendrimers with Metallacarboranes

A new family of polyanionic poly(alkyl aryl-ether) metallodendrimers decorated with four and eight cobaltabisdicarbollide units have been obtained in high yield by the ring-opening reaction of cyclic oxonium [3,3′-Co(8-(C₂H₄O)₂-1,2-C₂B₉H₁₀)(1′,2′-C₂B₉H₁₁)] with alkoxides formed by deprotonation of terminal alcohols.


HPLC detection time for several sizes of metallodendrimers

Fast microwave assisted synthesis of carbon xerogels

2012-04-20T15:46:43+00:00

Fast microwave-assisted synthesis of tailored mesoporous carbon xerogels

Resorcinol-formaldehyde carbon xerogels with several initial pH were synthesized using two different heating methods (conventional and microwave heating). The effect of the pH of the precursor solution and the method of synthesis employed on the textural and chemical properties of the final materials was evaluated. The figure shows a representation of the gelation point of several RF xerogels obtained by microwave heating from precursor solutions with different pHs.


Sol-Gel transition detection during the microwave baking of the RF solution by using a home-made DAQ for energy consumption

Carbon xerogel/multiwalled carbon nanotubes composite supercapacitors

2012-04-19T15:50:07+00:00

Electrochemical behavior and capacitance properties of carbon xerogel/multiwalled carbon nanotubes composites

The electrochemical behavior of carbon xerogel/multiwalled carbon nanotubes composite in a 6 M KOH solution has been investigated. Three different mixtures of teflonized carbons with varying nanotube content were prepared. The electrodes containing multiwalled carbon nanotubes were found to provide enhanced capacities compared with those prepared with only carbon xerogel. Cyclic voltammetry and charge-discharge experiments reveal the presence of a strong resistive component, which decreases as the amount of nanotubes increases. Electrochemical impedance spectroscopy results analyzed in terms of an adequate physicochemical model of the porous electrode, show that an increasing amount of nanotubes enhances both the effective solid-phase conductivity and the effective liquid-phase conductivity, linked to the porosity of the electrodes.


TEM figures of the composite material

Carbon xerogel - manganese oxide advanced supercapacitors

2012-04-13T15:44:41+00:00


Capacitance vs. V curves for carbon xerogel-based supercapacitors

Carbon Xerogel and Manganese Oxide Capacitive Materials for Advanced Supercapacitors

Symmetric supercapacitors (SSC) and asymmetric supercapacitors (ASC) that use carbon xerogels with different porous textures as negative electrode and manganese oxide as positive electrode were investigated. Figure shows the capacitance curves versus potential for these carbon xerogel-based supercapacitors. Voltage sweep rate:10 mVs⁻¹.

Ball lightning and plasma arc formation during the microwave heating of carbons

2012-04-12T15:43:40+00:00


Plasma ball and arc formation during the microwave heating of carbons

Ball lightning plasma and plasma arc formation during the microwave heating of carbons

Photographic evidence of plasma formation when different carbon materials are subjected to microwave heating is presented. Two different kinds of plasmas are observed: ball lightning and arc discharge plasmas. The intensity of the plasmas in the less ordered carbon was significantly higher at the beginning of the process.

Oxidative Addition of Interhalogens to Organodiselone Ligands

2012-04-11T15:48:33+00:00


Reaction scheme depicting formation of X-Se-I T-shaped adduct, bond paths and BCPs of compound I-Se-Br, contour plot of the Laplacian of the electron density and ELF domains.

A Unique Case of Oxidative Addition of Interhalogens IX (X=Cl, Br) to Organodiselone Ligands: Nature of the Chemical Bonding in Asymmetric I-Se-X Polarised Hypervalent Systems

Unprecedented “T-shaped” adducts featuring I-Se-X moieties (X = Cl, Br) have been obtained from the oxidative addition of interhalogens IX to organoselone donors, Atom in Molecules (AIM) and Electron Localization Function (ELF) topological approaches have been used to ascertain the hypervalent nature of the chalcogen atom in these unusual three-body systems. New criteria of analysing hypervalency in these and related systems are proposed.

Our cover for Chem Soc Rev

2012-04-11T12:11:05+00:00

So far so close pareidolia.

DFT geometry optimization of cobaltabisdicarbollide [3,3-Co-(1,2-C₂B₉H₁₁)₂]^- anion structure using B3LYP/6-31+g(d,p) hybrid functional. The transparent balls and sticks model is rendered using the diamond index of refraction (2.4) for the objects and superimposed on the picture of the lenticular galaxy Fornax A. This composition is the front cover for the Volume 41 Issue 9 of Chem Soc Revs (2012)

Background Image of Fornax A licensed for use under the Creative Commons Attribution 3.0 from National Radio Astronomy Observatory (NRAO), Associated Universities, Inc. (AUI) and J. M. Uson. Image composition original idea: M. Lepsik. Design (Povray): Emilio J. Juarez-Perez.

Metallacarboranes and their interactions

2012-04-11T12:02:00+00:00

Metallacarboranes and their interactions: theoretical insights and their applicability

Metallacarbaboranes (or metallacarboranes) are a class of inorganic polyhedral clusters containing carbon, boron, hydrogen, and metal atoms in various combinations. Metallacarboranes are becoming subject of growing interest to the broad chemical community owing to their unique combination of features and properties including the rigidity of the cages and their relative rotary motion, hydrophobicity, as well as chemical and thermal stability due to delocalized charge. The inclusion of carbon atoms in the boron framework causes a differential reactivity of the cluster with either acidic (carbon-bound) or hydridic (boron-bound) hydrogen atoms.


X-ray structure of the complex between HIV-1 protease and [3,3-Co-(1,2-C₂B₉H₁₁)₂] metallacarborane

Phosphorous-containing Cobaltabisdicarbollide Derivatives on Titania Surface

2012-04-10T15:40:00+00:00


Two ways of anchoring the cobaltabisdicarbollide anion on TiO₂ surface nanoparticles

Anchoring of Phosphorous-containing Cobaltabisdicarbollide Derivatives to Titania Surface

Cobaltabisdicarbollide derivatives have been anchored for the first time to the surface of TiO₂ particles using two phosphorous-containing moieties.

SOFT - G3data

2012-03-29T11:59:00+00:00

Utilidades: G3data

G3data¹ se utiliza para extraer los datos de los gráficos en figuras. En las publicaciones se suelen incluir gráficos, pero faltan los datos reales. Con G3data, el proceso de extracción de estos datos es sencillo y el programa puede leer muchos formatos de imagen diferentes.

A continuación se muestra un uso práctico del programa.

Durante la pasada huelga del 29 de marzo (2012), muchos medios y páginas webs comenzaron a seguir los datos de REE sobre demanda de energía electrica para medir el seguimiento que estaba teniendo dicha huelga. Por ejemplo: éste, éste y éste.

Los resultados que ofrecen son bastante dispares (e incluso contradictorios entre sí, por ejemplo entre los dos primeros). Aunque en general la metodología es buena, creo que en ningún momento se está integrando áreas bajo la curva de demanda. Entonces, he decidido hacer mi propia cuantificación usando G3data y comparar demandas durante esta huelga y la del 29/9/2010.

Se podría considerar que existe un 100 % de seguimiento de la huelga si la demanda presenta una curva similar a la de un domingo (por ejemplo el domingo anterior) y un seguimiento del 0% si la curva integrada es similar a la del dia anterior a la huelga.

Los gráficos que proporciona REE son muy atractivos visualmente y bastante interactivos.


Demanda en MW. Fuente: REE.

Pero a la hora de intentar extraer los datos en crudo resulta tedioso hacerlo directamente del gráfico. Desconozco si hay otra forma de hacerlo que resulte más sencillo pero con G3data el proceso de extraer datos de los gráficos es trivial.

Su uso es bastante sencillo, primero imprimimos la pantalla a un fichero en formato imagen (png, tiff). Segundo, se indican donde están situados los ejes x e y del gráfico y se define su escala. Finalmente, con la herramienta zoom vamos marcando con clics de ratón la curva con la precisión que se desee, por ejemplo con unos 100 puntos por línea.

En la siguiente figura se muestran las gráficas extraidas usando G3data, el día previo a la huelga, el domingo previo, el día de la huelga actual y el dia del huelga del 29/09/2010.


Demanda en MW. Fuente: REE.

Con los datos extraidos integramos las áreas bajo la curva obteniendo energía consumida entre las 0-24 horas en MWh como mostrado en la siguiente tabla:

Día	Consumo (MWh)
Domingo previo 25	581.2
Miércoles 28 (día previo)	689.3
Jueves 29 (huelga)	592.4
anterior huelga (29/9/2010)	604.6

Con estos datos obtenemos una estimación del seguimiento de la huelga del 29/3/2012 y la 29/09/2010 de aproximadamente 89 y 78 %, respectivamente.

The original G3data was fetched from http://www.frantz.fi/software/g3data.php. Now G3data is available as a Debian package. ↩

Carboranyl Substituted Siloxanes and Octasilsesquioxanes

2012-03-27T14:40:00+00:00


Carboranyl-containing cage-like silsesquioxane

Carboranyl Substituted Siloxanes and Octasilsesquioxanes: Synthesis, Characterization, and Reactivity

Carboranyl-containing disiloxane, cyclic-siloxane and cage-like silsesquioxane (figure) have been prepared in high yields. Two routes are compared for their preparation, a classical hydrolytic process based on hydrolysis and condensation of the freshly prepared carboranylalkylchlorosilane and ethoxysilane precursors and a nonhydrolytic route based on the specific reactivity of chorosilane toward DMSO. Based on the typical reactivity of the carboranyl group toward nucleophiles, dianionic disiloxanes and octaanionic silsesquioxanes were obtained without modification of the siloxane bond. Products are fully characterized by FTIR, NMR and MALDI-TOF methods.

Carboranyl-containing

Controlled Direct Synthesis of C-Mono- and C-Disubstituted Derivatives of Cosane

2012-03-26T00:00:00+00:00


Pov-ray render of C mono-substituted cobalta-bis-dicarbollide crystal structure

Controlled Direct Synthesis of C-Mono- and C-Disubstituted Derivatives of [3,3′-Co(1,2-C₂B₉H₁₁)₂]⁻ with Organosilane Groups: Theoretical Calculations Compared with Experimental Results

The first C-mono and C-disubstituted cobaltabis(dicarbollide) derivatives containing different organosilane functions have been successfully prepared by the direct reaction of the mono- or dilithium salts of the [3,3′-Co(1,2-C₂B₉H₁₁)₂]⁻ and [8,8′-μ-(1′′,2′′-C₆H₄)-3,3′-Co(1,2-C₂B₉H₁₀)₂]⁻ ions with the appropriate chlorosilanes under temperature control.

Formation of a Si-C bond from an intramolecular Si-H···H-C diyhydrogen interaction

2012-03-25T14:49:00+00:00


Clamping dicarbollides

First example of the formation of a Si-C bond from an intramolecular Si-H···H-C diyhydrogen interaction in a metallacarborane: A theoretical study.

The Quantum Theory of Atoms in Molecules of Bader (QTAIM) at different levels of theory (B3LYP/6-311(d,p) and BP86/TZ2P(+)) has been used to study the H···H interactions found in the crystal structure of [1-SiMe₂H-3,3′-Co(1,2-C₂B₉H₁₀)(1′,2′-C₂B₉H₁₁)]⁻. The two Si–H···H–C contacts are interpreted as an asymmetric bifurcated dihydrogen bond (DHB) defining the H···H interactions and explain the formation of [1,1′-μ-SiMe₂-3,3′-Co-(1,2-C₂B₉H₁₀)₂]⁻.

LATEX - plantilla para una presentación usando Beamer

2010-06-12T18:00:00+00:00

Una vez preparada la tesis (ver post anterior) necesitarás presentarla. Para ello usaremos también L^AT_EX, en concreto el paquete Beamer.

Aquí te puedes descargar la plantilla (main.tex) y el .pdf generado que hice para mi presentación.

LATEX - plantilla para tesis doctoral por compendio de artículos

2010-06-12T17:54:45+00:00

Esta plantilla está basada en la plantilla itsas_thesis_template.es.r23.tar.gz con modificaciones simples para adaptarla a los requerimientos del departamento de Química de la UAB (2009).

Instalando L^AT_EX.

Esta primera parte está dedicada a la instalación de L^AT_EX. Si ya lo tienes instalado puedes ir al siguiente apartado donde se explica como usar la plantilla.

Mi ordenador tiene una Debian 5 (Lenny) aunque los pasos que se exponen a continuación deben ser válidos para toda distro moderna.

Para crear código L^AT_EX que luego compilaremos realmente sólo se necesita un editor de textos tipo “bloc de notas”, sin embargo existen entornos como “kile” que facilitan el trabajo de edición de estos ficheros .tex

  $ sudo aptitude install kile

Tras instalar kile procedemos con la instalación de L^AT_EX. Es recomendable instalar estos paquetes y todos los que sugiera aptitude,

    $sudo aptitude install texlive texlive-LATEX-extra texlive-science texlive-lang-spanish

Además de todo lo instalado anteriormente se necesitan dos paquetes de L^AT_EX que no he podido localizar en paquetes de debian. Sin embargo es sencillo conseguirlos en CTAN. Los paquetes en cuestión son mciteplus y notes2bib:

    $wget [http://www.ctan.org/get/macros/LATEX/contrib/mciteplus.zip](http://www.ctan.org/get/macros/LATEX/contrib/mciteplus.zip)
    $wget [http://www.ctan.org/get/macros/LATEX/contrib/notes2bib.zip](http://www.ctan.org/get/macros/LATEX/contrib/notes2bib.zip)

descomprimimos los .zip

y dentro de la carpeta notes2bib debemos generar el fichero .sty de la siguiente manera:

    $latex notes2bib.ins

tras esto llevamos a /usr/share/texmf/tex/latex/ las dos carpetas para tenerlos disponibles para todo el sistema,

    $sudo cp -r mciteplus /usr/share/texmf/tex/latex/
    $sudo cp -r notes2bib /usr/share/texmf/tex/latex/

finalmente hacemos el update de los paquetes de L^AT_EX

    $sudo texhash

A continuación abrimos kile y ya estamos listos para utilizarlo. Pero antes, para poder usar correctamente la plantilla de la tesis tenemos que configurar kile para que use de codificación iso-8859-15 en lugar de la utf8 que usa por defecto. Todos los ficheros .tex de esta plantilla están en la primera codificación y se usa \usepackage[latin1]{inputenc} para poner acentos y caracteres especiales del castellano como las eñes. Si abrimos un fichero .tex codificado como iso-8859-15 en un kile con utf8 veremos que tildes y eñes han sido sustituidas por símbolos de interrogación. En Settings - configure kile… - editor – open/save y en file format y en encoding seleccionamos iso-8859-15 y guardamos. Ya está todo preparado.

Como usar esta plantilla de L^AT_EX.

Descargamos el fichero TESIS-plantilla.tar.bz2 y lo descomprimimos. La carpeta contiene 18 ficheros tipo .tex, 1 fichero .bib (la bibliografía), una carpeta llamada Config (con ficheros de configuración) y una carpeta donde se guardan las figuras que se vayan a utilizar para la elaboración del documento.

El documento maestro de esta plantilla se llama PRINCIPAL.tex. Podemos abrir este fichero en kile e ir leyendo para ver como está estructurado. Este fichero PRINCIPAL.tex es el que compilaremos para generar el pdf. Mediante órdenes include se incorporan a PRINCIPAL.tex el resto de secciones y capítulos (otros ficheros .tex) que formarían la tesis.

La normativa obliga a que este documento tenga algunas partes de obligada inclusión. Básicamente la tesis la conforman los siguientes apartados:

1portada.tex ( portada con logos en ciertas posiciones, título, autor, director…)
2certificado-extra.tex (certificado que exige el departamento)
2certificado.tex (certificado que ponemos en el CSIC, con membrete)
3financiacion.tex (hoja donde se indican las becas…etc)
4agradecimientos.tex (las hojas de agradecimientos)
5prefacio.tex (donde se explica que la tesis es por artículos y se relacionan los que pasaron la comisión)
6figurascompuestos.tex (hojas con los esquemas de los compuestos)
7abreviaturas.tex (hoja de abreviaturas)
8resumen.tex (un resumen de la tesis)
9toc.tex (el indice general, este fichero no hay que rellenarlo con nuestros datos simplemente es un fichero de configuración para generar automáticamente el índice. Con un include a este fichero en PRINCIPAL.tex indicamos la posición del índice en la tesis)
x1-Introduccion.tex (capítulo con la introducción)
x2-Objetivos.tex (capítulo con los objetivos)
x3-RYD.tex ( primera hoja indicando el comienzo de Resultados y Discusion)
x4cap.tex (primer capítulo de RyD, crear cuantos sean necesarios y hacer un include en PRINCIPAL.tex donde corresponda)
x7-Conclusion.tex (hojas con las conclusiones
x8-Publicaciones-A.tex (las publicaciones que pasen la comisión son un capítulo de la tesis, las otras publicaciones que queramos incluir deben ir en un anexo, ver x9-Publicaciones-B.tex)
x9-Publicaciones-B.tex (anexo con otras publicaciones)
tesis.bib (este fichero contiene las referencias en formato bibtex, recomiendo JabRef como base de datos para referencias en bibtex)

Una vez seleccionado PRINCIPAL.tex como documento maestro en kile, generamos el pdf. Si todo fue bien instalado se debería de producir un pdf de unas 60 páginas donde he dejado algunas figuras, una tabla y citas en el texto a modo de ejemplo. Ya sólo queda ir rellenando cada fichero .tex con tu material y una vez compilado obtener un .pdf con la tesis.

La inclusión de los artículos en la tesis merece un inciso especial. Lo más fácil sería una vez obtenido el pdf de la tesis ir anexando en ese mismo pdf los ficheros pdf que corresponden a los artículos, pero esto rompería la paginación, cabeceras, pies de página etc. Un método más apropiado para incluirlos en el documento fue deshacer cada pdf con un artículo en sus hojas por separado también en formato .pdf. (recomiendo el paquete pdftk para hacer esto). De esta manera, incluiremos cada hoja de los artículos una a una como si fueran figuras con la orden correspondiente (ver x9-Publicaciones-B.tex por ejemplo) He dejado la primero página de alguno de los artículos para que se entienda el proceso. Cada hoja de cada artículo debe ser guardada en el lugar correspondiente dentro de la carpeta figuras.

LATEX - plantilla para currículum normalizado del MICINN

2010-05-30T18:05:56+00:00

Actualización 7 Oct 2015: no uses esta plantilla para presentar un CV en alguna convocatoria oficial. En su lugar crea un CV normalizado usando la aplicación CVN de FECYT

Esta plantilla es una modificacion para obtener una plantilla de CV (en inglés) para solicitar la beca Juan de la Cierva (2010).

Los ficheros originales para hacer este CV normalizado del ministerio son de Juan Luis Varona (ver fichero leeme.txt para más información).

Los ficheros cvEnJdC.cls y cv_normalizado_english.tex son una modificación ligera y sucia de curriCICT2000.cls para adaptar el CV a la convocatoria Juan de la Cierva 2010. En concreto se ha adaptado para presentar el CV en inglés, se ha añadido el logotipo de MICINN para obtener un pdf lo más fiel posible al original, también se han modificado algunas macros del fichero .cls. y la fuente que se usa para rellenar los campos.

Para crear tu cv primero asegúrate de que la plantilla compila bien en tu sistema. Luego sigue las instrucciones del fichero .tex.

Bajar plantilla cvEnJdC.

Cobaltabisdicarbollide rotamers

2010-01-10T14:52:00+00:00

Rotámeros transoid-gauche-cisoid del anión cobaltabisdicarballuro

Cálculos realizados con ADF 2007. BP86/TZ2P(+)


Momento dipolar dependiente de la rotación relativa de los ligandos dicarballuro


Niveles de energía


Orbital molecular HOMO para el rotámero cisoide


Mapeado del potencial electrostático para el rotámero cisoide

Poster presentado en el 13^th International Meeting in Boron Chemistry (Imeboron 13)


Solid State Interactions between Tetramethylammonium and Cobaltabisdicarbollide. Experimental and Computational Studies
E. J. Juárez-Pérez, R. Núñez, C. Viñas, F. Teixidor, R. Sillanpää, R. Kivekäs

Descárgalo en .pdf aquí.

CLI - Generación de tarjeta de acreditación para congresos

2009-07-06T17:44:21+00:00

En el post anterior se vió como se extraía la información necesaria de documentos .doc. El siguiente script sirve para automatizar la generación de las tarjetas de identificación (acreditaciones) de los participantes del congreso.

Situacion: Se necesitan imprimir unas 300 tarjetas con el nombre, organización y pais para los participantes de un congreso, acompañantes, y staff… unas 300 acreditaciones aproximadamente.

Este script requiere el paquete imagemagick. Pide de entrada un archivo .csv (o texto plano) con los siguientes campos separados por comas:PAIS,APELLIDOS,NOMBRE,ORGANIZACION y el modelo de plantilla de acreditación por ejemplo acreditación de “staff”, “participante” o “acompañante” etc.

El resultado es una carpeta llena de ficheros .png de tamaño folio con acreditaciones “cara” y “reverso” idénticas listas para imprimir.

#!/bin/bash
#
#
# Anyone may run this program.  Modification and Distribution of this program are licensed by the author subject to the terms of the Gnu Lesser General Public License.
# You can find the license text here:  http://www.gnu.org/licenses/lgpl.html
# Lee el fichero $INPUT que es un csv separado por comas con
# Pais, Nombre y Apellidos y crea las acreditaciones basadas
# en la plantilla
echo "fichero de lectura?"
read INPUT
echo "tipo de acreditación:"
echo "acomp,staff,part?"
read ACRED
# inicialización de variables.
FONT=../fuentes/VAGROUN.TTF
COLOR1='rgb(49,77,99)'
COLOR2='rgb(253,114,23)'
TARJETAS=$(wc -l < $INPUT)
FOLIOS=$(( $TARJETAS/3 + 1))
#
echo $FOLIOS
# crea carpeta donde van a ir todas las acreditaciones
mkdir folios-$INPUT
sed 's/ ,/,/g' $INPUT | sed 's/, /,/g' | sed "s/'/\\\'/g" | sed 's/,/, /g' > lista
mv lista folios-$INPUT
#
# crea los folios de las acreditaciones, 3 para cada uno.
NFOLIOS=1
while [ $NFOLIOS -le $FOLIOS ]; do
cp $ACRED.png folios-$INPUT/$NFOLIOS.png
let NFOLIOS=$NFOLIOS+1
done
cd folios-$INPUT
#
#
#
LIMIT=$FOLIOS
for ((NFOLIOS=1; NFOLIOS <= LIMIT ; NFOLIOS++))  
do
#nombre y apellidos $3$2
convert $NFOLIOS.png -fill $COLOR1 -font $FONT -pointsize 94 -draw "text 80,847 '$(awk -F, 'NR=='3*$NFOLIOS-2' {print($3 $2)}' lista)'"\
"text 1290,847 '$(awk -F, 'NR=='3*$NFOLIOS-2' {print($3 $2)}' lista)'"\
"text 80,1763 '$(awk -F, 'NR=='3*$NFOLIOS-1' {print($3 $2)}' lista)'"\
"text 1290,1763 '$(awk -F, 'NR=='3*$NFOLIOS-1' {print($3 $2)}' lista)'"\
"text 80,2678 '$(awk -F, 'NR=='3*$NFOLIOS' {print($3 $2)}' lista)'"\
"text 1290,2678 '$(awk -F, 'NR=='3*$NFOLIOS' {print($3 $2)}' lista)'" $NFOLIOS.png
#pais $1
convert $NFOLIOS.png -fill $COLOR1 -font $FONT -pointsize 94 -draw "text 94,1076 '$(awk -F, 'NR=='3*$NFOLIOS-2' {print$1}' lista)'"\
"text 1304,1076 '$(awk -F, 'NR=='3*$NFOLIOS-2' {print$1}' lista)'"\
"text 94,1992 '$(awk -F, 'NR=='3*$NFOLIOS-1' {print$1}' lista)'"\
"text 1304,1992 '$(awk -F, 'NR=='3*$NFOLIOS-1' {print$1}' lista)'"\
"text 94,2908 '$(awk -F, 'NR=='3*$NFOLIOS' {print$1}' lista)'"\
"text 1304,2908 '$(awk -F, 'NR=='3*$NFOLIOS' {print$1}' lista)'" $NFOLIOS.png
#organización $1
convert $NFOLIOS.png -fill $COLOR2 -font $FONT -pointsize 44 -draw "text 90,958 '$(awk -F, 'NR=='3*$NFOLIOS-2' {print$4}' lista)'"\
"text 1300,958 '$(awk -F, 'NR=='3*$NFOLIOS-2' {print$4}' lista)'"\
"text 90,1874 '$(awk -F, 'NR=='3*$NFOLIOS-1' {print$4}' lista)'"\
"text 1300,1874 '$(awk -F, 'NR=='3*$NFOLIOS-1' {print$4}' lista)'"\
"text 90,2790 '$(awk -F, 'NR=='3*$NFOLIOS' {print$4}' lista)'"\
"text 1300,2790 '$(awk -F, 'NR=='3*$NFOLIOS' {print$4}' lista)'" $NFOLIOS.png
echo "numero de folio=$NFOLIOS"
done
#rm -f /home/ejjuarez/DOCUMENTACION-LINUX/MY-macros-scripts/acreditaciones-imeboron/folios/$INPUT
#
#
#
#

En la figura de abajo se puede ver el resultado, las dimensiones son aproximadamente 8x10 cm:


Ejemplo de acreditación generada para el IMEBORON XIII

Actualización 7 Dec 2017: con modificaciones triviales a este script se puede automatizar la generación de certificados


Ejemplo de certificado generado para el ISEST2018

CLI - Extracción de datos de ficheros formulario word

2009-07-06T17:44:21+00:00

Este script se utilizó en un caso real para automatizar la extracción de información de archivos .doc usados a modo de formulario.

El caso real son unos 200 ficheros .doc tipo abstracts para un congreso. Cada uno de ellos consistía de una sola hoja con Título del poster/conferencia, Autores, Fotografía del autor principal, resumen y referencias. Con los datos extraidos se crearon hojas de cálculo o CSVs para facilitar la creación de listados por paises, direcciones de correo, instituciones, etc.

El formato .doc no es amigo de la línea de comandos y previo a todo procesado, los ficheros .doc se convirtieron a texto plano .txt usando la macro de Danny Brewer para convertir en batch documentos de un formato a otro.

Actualización 7 Oct 2018: posiblemente el paquete pandoc sea una buena alternativa a esta macro

Si el formulario se rellenó siguiendo las instrucciones, el archivo .txt contendría unas determinadas líneas con la información bien localizada. El siguiente paso es aplicarle el script detallado más abajo para extraer los datos que necesitamos de esos 200 ficheros de tipo txt. Mucha gente tiene problemas para seguir unas instrucciones paso a paso, quizás porque dichas instrucciones son ambiguas o quizás gusta de romper las normas cuando esto no tiene realmente consecuencias sin descartar que simplemente dicha persona sea un poco faltusca. Aproximadamente el 25 % de los formularios recibidos necesitaron de alguna correción manual.

El script usa sed, awk, head, tail,… comandos estándar en distribuciones GNU-linux, y está dividido en cuatro partes:

La primera parte crea el archivo TITLES.CSV que da correspondencia entre títulos y un numero identificativo que queda grabado en el fichero lista.
La segunda parte crea AUTHORS.CSV y en este caso da correspondencia entre autores y el número de abstract de lista.
La tercera parte es la más difícil. Extrae uno a uno todos los autores y le da correspondencia con el abstract que presentan. La dificultad reside en el número de autores variable para cada abstract y su composición que puede ser Nombre + 2 apellidos o +1 apellido, 2 nombres un apellido, 2 nombres + 2 apellidos etc. El script 3 recoge casi toda la casuística pero contra los John Smith III Jr., el nexo “der” o los apellidos de alto abolengo unidos por “de”, el script fallará miserablemente. Se recomienda no enmendar este error manualmente o incluso empeorarlo, si es posible, con algún juego de palabras. La función de este tercer script es generar el fichero INDEX.CSV con filas de Apellido, Nombre de tal forma que contiene todos los autores y todos los abstracts correspondientes en los que Apellido, Nombre aparece como autor.
La cuarta parte del script relaciona autores y títulos.

#!/bin/bash
# Script para el ImeboronXIII que extrae la informacion de los "Abstracts" en
# formato .doc y crea listados .csv's mucho más útiles ;)
# Este script come archivos de texto plano, por ejemplo tipo .txt. Para convertir en batch los .doc en 
# ficheros .txt se puede utilizar la macro de
# Danny Brewer(2003) modified by Dan Horwood, 05/2006, to support new OpenDocument files..  All rights reserved.
# 
# Anyone may run this program.  Modification and Distribution of this program are licensed by the author subject to the terms of the Gnu Lesser General Public License.
# You can find the license text here:  http://www.gnu.org/licenses/lgpl.html
#
#
# Renombra todos los archivos .txt quitando espacios.
rename 's/ //g' *txt
#
#...............script1.........................
#
#
#se crea el archivo "lista" y se obliga a introducir el número de archivos que hay.
ARCHIVOS=`ls *txt -1 > lista`
nl lista
echo "numero de archivos?"
read NUMARCHIVOS
#
# rutina para la creacion de correspondencia entre numero de poster/presentacion..etc y su título
NUM=1
rm -f TITLES.csv
while [ $NUM -le $NUMARCHIVOS ]; do
ARCHIVOTXT=`head -$NUM lista | tail -1`
TITLE=`head -1 $ARCHIVOTXT | tail -1` 
echo "P"$NUM"% "$TITLE >> TITLES.csv
let NUM=$NUM+1
done
#
#...............script2.........................
#
#
# rutina para la creacion de correspondencia entre numero de poster/presentacion..etc y sus autores.
NUM=1
rm -f AUTHORS.csv
rm -f O-names.csv
#
while [ $NUM -le $NUMARCHIVOS ]; do
ARCHIVOTXT=`head -$NUM lista | tail -1` 
NAMES=`head -3 $ARCHIVOTXT | tail -1` 
#
echo "P"$NUM"@ "$NAMES >> O-names.csv
let NUM=$NUM+1
done
#
# Quitamos con sed el típico 'and' del último y penúltimo autor. Cambiamos comas por %. Añadimos % al final de linea
# y quitamos puntos.
#
sed 's/ and /% /g' O-names.csv > 1-names.csv
sed 's/, /% /g' 1-names.csv > 2-names.csv
sed 's/$/%/g' 2-names.csv > 3-names.csv
sed 's/\.//g' 3-names.csv | sed 's/,//g' | sed 's/ % /% /g' > 4-names.csv
#Falta añadir un sed que ponga puntos en las abreviaturas de los segundos nombres.
rm O-names.csv
rm 1-names.csv
rm 2-names.csv
rm 3-names.csv
mv 4-names.csv AUTHORS.csv
#
#
#...............script3.........................
#
#
# 
# el awk: la joya.
rm -f INDEX.csv
awk '{ for (i = NF; i > 2; i--) 
if ($i ~ /%/ && $(i-2) !~ /%/ && $(i-2) !~ /@/) print($1" "$i", "$(i-2)" "$(i-1))}
{ for (i = NF; i > 2; i--) 
if ($i ~ /%/ && $(i-2) !~ /%/ && $(i-2) ~ /@/) print($1" "$i", "$(i-1))}
{ for (i = NF; i > 2; i--)
if ($i ~ /%/ && $(i-2) ~ /%/) print($1" "$i", "$(i-1)) }' AUTHORS.csv | sed 's/@/,/g' | sed 's/%//g' > INDEX.csv
#
#
#...............script4.........................
#
#
# 
# union de Titles y Authors para dar un csv sin número
paste --delimiters="%" TITLES.csv AUTHORS.csv | sed 's/@/%/g' > TA.csv

Polyanionic Carbosilane and Carbosiloxane Metallodendrimers

2009-02-16T14:52:00+00:00

Article: Polyanionic Carbosilane and Carbosiloxane Metallodendrimers Based on Cobaltabisdicarbollide Derivatives

Carbosilane and carbosiloxane metallodendrimers that contain one, four, and eight peripheral cobaltabisdicarbollide derivatives have been synthesized using regiospecific hydrosilylation of vinyl-terminated dendrimers with Cs[1,1′-μ-SiMeH-3,3′-Co(1,2-C₂B₉H₁₀)₂]


3rd Generation Carbosilane Metallodendrimer


1st Generation Carbosiloxane Metallodendrimer

Notes:

Skeletal ciclocarbosiloxane/carbosilane dendrimers is geometry optimized with PM6 semiempirical method Mopac2007.
Cobalbisdicarbollide anions are apart optimized with DFT methods B3LYP/6-311G(d,p) Gaussian03
Povray file is generated with Gabedit

Utilidades - Calculadora de pesos moleculares

2009-02-16T08:35:10+00:00

Fuente original del código java de esta calculadora: aquí

Pesos atómicos usados: Pure Appl. Chem., 78, 2051-2066 (2006)

ejemplo: Cu(CH2H3O2)2H2O

Utilidades - Conversión de unidades de energía

2009-02-16T08:35:10+00:00

Fuente original del código: aquí

Energy Units Converter

Enter your energy value in the box with the appropriate units, then press “tab” or click outside of the input box.