El País Valencià ha renascut de les seues cendres

25 05 2015

Mira si he corregut terres que he estat en Alfarrasí, entre Adzaneta i Albaida, en el Palomar i ací.

Vinc del cor de la Costera, del poble dels socarrats, d’allà on renaix de les cendres el meu País Valencià.





Entrevistas a investigadores

20 05 2015

Nuestro centro se encuentra frente al reto de llevar la ciencia a todos los estudiantes para su formación como futuros ciudadanos responsables y preparados para la toma de decisiones, intentando, a su vez, no caer en la transmisión de una imagen deformada de la ciencia que generan el desinterés y el rechazo. Por lo tanto, la iniciativa aquí expuesta perseguía un objetivo fundamental: que los alumnos reflexionasen sobre la actividad científica y sobre las visiones que de ésta tienen investigadores expertos en diferentes campos de la ciencia. El proyecto se expone a continuación:

Entrevistamos a Científicos de Excelencia

Los alumnos de 1º Bachillerato de la asignatura de Ciencias del Mundo Contemporáneo tuvieron la oportunidad de tener un primer contacto vía correo electrónico con investigadores de prestigio internacional, reconocidos por sus investigaciones punteras en diferentes campos de la ciencia. Para esta actividad, ambos grupos por consenso confeccionaron una carta de presentación del proyecto y elaboraron una serie de preguntas para cada investigador. En horas de clase pudimos adentrarnos en los campos de investigación, obteniendo información a través de internet tanto del centro de investigación como de la trayectoria de los científicos.

Proyecto dirigido por Daniel García Velázquez, Doctor en Ciencias Químicas (Química Orgánica) Universidad de La Laguna





The battle against rooftop solar

20 05 2015

After many years of incentives, subsidized prices, and support policies, the drop of prices of photovoltaic solar panels has become a reality. The price of a 6 kilowatt system in USA is about $20,000 and it is increasingly attractive to install solar energy in your house to produce the electricity that you need, straight from sunlight. If this move becomes a massive one, it may become a major step towards a more environmental friendly energy production system. Energy will be produced with very low carbon emission cost (that made when producing the solar cells) and in a decentralized way, so that everyone will manage their own energy. The rooftop panel can be connected to the electricity grid to obtain electricity when the sun doesn’t shine, and the surplus of solar energy produced in the house can be fed to the grid, inverting the counter and creating credit for the owner. Another major step has occurred a few weeks ago when Tesla announced the commercialization of a very attractive home battery that can store the electricity. In this way the house may become completely independent of the electricity grid. According to Emily Barone, writing in Time last week, the demand for rooftop solar panels is heating up: a record 187,000 U.S. homeowners installed solar panels in 2014.

However, this silent revolution is not pleasing everybody. The utilities are fearing that they will loose a lot of clients, so they are opposing fiercely the decentralized system. A strong campaign has been launched in many US states in order to impose penalties to self production, with the argument that the absent people should also contribute to sustain the grid. In Spain, right-winged PP government has repeatedly announced that it will take measures to charge heavily self production of solar energy in the houses. This is not surprising, since former top politicians of all signs now serve as advisors of the major utilities (this is one prominent example of so-called “revolving doors”). In Spain, with such abundance of solar irradiation, the notion that one should pay to juice the sunlight is strikingly odd to a majority of the population. But a few people with mega-salaries can do a great job at protecting the interest of a few. If such thing happens, it will not be a total surprise .

More information:

Utilities wage campaign against rooftop solar

The alliance for solar choice





nanoGe September Meeting 2015 Santiago de Compostela

7 05 2015

This unique serie of conferences have been organized with the aim of offering two intensive weeks full of exciting contents.

International Conference of Fundamental Processes in Semiconductor Nanocrystals (FQDots15)

Santiago de Compostela, Spain, 6-8 September 2015

Semiconductor nanocrystals (NCs), known for their tuneable electronic band structure, have been at the centre of significant interest over two decades, owing to potential application in various opto-electronic devices and biological platforms. NCs prepared via wet-chemical colloidal procedures are of particular current interest, due to cheap synthesis and scalable preparation of thin films. Despite intense research in the past decades, several basic fundamental issues are unknown. The nanoGe meeting will bring together speakers that will discuss current interest in this area

International Workshop on Ferroic Photovoltaics (FerroPV)

Santiago de Compostela, Spain, 9 September 2015

Ferroelectric materials produce permanent electrical fields and show great potential for photovoltaic applications. Currently both oxide and non-oxide perovskites with ferroelectric and semiconductor properties have produced important and encouraging results, however the mechanisms of Ferroic Photovoltaics are poorly understood yet. This workshop is the first monographic meeting on this exciting topic and will unite a number of outstanding experts. The format of the meeting encourages discussion in order to promote a public analysis of the physical mechanisms and materials properties of ferroelectric semiconductors for PV applications.

International Conference on Solution Processed Innovative Solar Cells (SPINS15)

Santiago de Compostela, Spain, 9-11 September 2015

The SPINS15 conference this year aims to summon world renowned experts in the fields of solution processed inorganic and hybrid thin film solar cells. This year’s conference content will make a balanced presentation in the progress of thin film solar cells with focus on Perovskite, Quantum Dot and nanocrystalline semiconductor solar cells, and Chalcopyrite/Kesterite (CZTS(Se), CI(G)S(Se)) thin film technologies as well as novel inorganic semiconductor compounds with exciting properties. The aim of this conference is to bring together scientists working in those material platforms to exchange knowledge, communicate challenges and potentially identify synergies amongst them

International Conference on Charge Transfer and Transport at the Nanoscale (CTTN15)

Santiago de Compostela, Spain, 13-15 September 2015

Unraveling the nature of charge transfer and transport processes taking place at the nanoscale is of pivotal interest for many different scientific disciplines. Furthermore, from a practical point of view, tuning charge transfer and transport through homo- or hetero-interfaces represents one of the key aspects for the further optimization of novel nanostructured-based applications (e.g. solar cells, batteries, sensors, electronics, catalyst,…). This nanoGe meeting will bring together experts from different fields in order to trigger interdisciplinary discussions and collaborations. We expect this conference to serve as a platform in order to share, advance and potentially unify methodologies and theories from different research sub-fields. Ultimately, the aim of the conference is to break the boundaries between chemistry, physics, biology and engineering concerning the nature of charge transfer and transport processes taking place at the nanoscale.





It is time to revolutionize the way we produce our energy

5 05 2015

Don´t you think it is time? If yes, then this project is for you !

This is a project led by renewable energy scientist Luca Bertoluzzi. The objective of this movie is to show in about two minutes how the way we produce our daily energy is affecting our environment and more generally mankind. This movie will leave no one indifferent and is aimed at making people think about the current situation and alternative solutions, without slipping into moralistic stereotypes.

But the movie has not been done yet, if you want to cooperate please look here.





Quantum dot solar cells with 8% efficiency

17 04 2015

Quantum dot layer solar cells have recently appeared in Tables with high (9%) efficiency. But here we show that quantum dot solar cells with TiO2 framework are also progressing rapidly and now show a certified 8% efficiency.

Furthermore this paper incorporates Enrique Canovas and Mischa Bonn to the previous team and we provide new fundamental insights with respect to the common image of injection and charge separation in the quantum dot solar cells

Boosting Power Conversion Efficiencies of Quantum-Dot-Sensitized Solar Cells Beyond 8% by Recombination Control

Ke Zhao, Zhenxiao Pan, Iván Mora-Seró, Enrique Cánovas, Hai Wang, Ya Song, Xueqing Gong, Jin Wang, Mischa Bonn, Juan Bisquert§, and Xinhua Zhong*
J. Am. Chem. Soc., Article ASAP
DOI: 10.1021/jacs.5b01946
Publication Date (Web): April 10, 2015
Copyright © 2015 American Chemical Society
ja-2015-019465_0007
At present, quantum-dot-sensitized solar cells (QDSCs) still exhibit moderate power conversion efficiency (with record efficiency of 6–7%), limited primarily by charge recombination. Therefore, suppressing recombination processes is a mandatory requirement to boost the performance of QDSCs. Herein, we demonstrate the ability of a novel sequential inorganic ZnS/SiO2 double layer treatment onto the QD-sensitized photoanode for strongly inhibiting interfacial recombination processes in QDSCs while providing improved cell stability. Theoretical modeling and impedance spectroscopy reveal that the combined ZnS/SiO2treatment reduces interfacial recombination and increases charge collection efficiency when compared with conventional ZnS treatment alone. In line with those results, subpicosecond THz spectroscopy demonstrates that while QD to TiO2 electron-transfer rates and yields are insensitive to inorganic photoanode overcoating, back recombination at the oxide surface is strongly suppressed by subsequent inorganic treatments. By exploiting this approach, CdSexTe1–x QDSCs exhibit a certified record efficiency of 8.21% (8.55% for a champion cell), an improvement of 20% over the previous record high efficiency of 6.8%, together with an additional beneficial effect of improved cell stability.




A Solid State Physics Perspective on Hybrid Perovskite Semiconductors

5 04 2015

The Journal of Physical Chemistry C is presenting a series of Feature Articles by key scientists about the fundamental properties of Hybrid Organic-Inorganic Halide Perovskites.

A Solid State Physics Perspective on Hybrid Perovskite Semiconductors

Jacky Even , Laurent Pedesseau , Claudine Katan , Mikaël Kepenekian , Jean-Sébastien Lauret ,Daniel Sapori , and Emmanuelle Deleporte
J. Phys. Chem. C,
DOI: 10.1021/acs.jpcc.5b00695

In this review we examine recent theoretical investigations on 2D and 3D hybrid perovskites (HOP) that combine classical solid-state physics concepts and density functional theory (DFT) simulations as a tool for studying their optoelectronic properties. Such an approach allows one to define a new class of semiconductors, where the pseudocubic high temperature perovskite structure plays a central role. Bloch states and k.p Hamiltonians yield new insight into the influence of lattice distortions, including loss of inversion symmetry, as well as spin-orbit coupling. Electronic band folding and degeneracy, effective masses and optical absorption are analyzed. Concepts of Bloch and envelope functions, as well as confinement potential are discussed in the context of layered HOP and 3D HOP heterostructures. Screening and dielectric confinements are important for room temperature optical properties of 3D and layered HOP, respectively. Non-radiative Auger effects are analyzed for the first time close to the electronic band gap of 3D hybrid perovskites.








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