Perovskites Used in Fuel Cells

Fuel cells are devices for energy generation with very high theoretical efficiency. Many researches were been carried out in the last few decades in order to develop reliable fuel cells. Solid oxide fuel cells (SOFC) and polymeric exchange membrane fuel cells (PEMFC) are those with more potential for commercial use. Specially for SOFC cathodes, many perovskites have been proposed as potential materials for this application. Nevertheless, other components of SOFC, such as the electrolytes, anodes and interconnects, have also been targeted with potential perovskites. More recently, the use of perovskites in PEMFC has also been proposed and studied. As many perovskite compositions can be used in SOFC components, some of the most important are discussed in this chapter and some recent works in perovskites for PEMFC are also referred. As a whole, in this chapter, the reader will find the relationship between the properties of perovskites with their compositions and the main effects of dopant agents regarding the utilization of these materials in different components of SOFC and in electrodes of PEMFC

Deposition of nanostructured LSM perovskite thin film on dense YSZ substrate by airbrushed solution combustion (ASC) for application in SOFC cathodes

[EN] To make SOFC high efficiency energy generation devices, thin ceramic films are proposed as their main components. The rate of the oxygen reduction reaction is relevant for the overall performance of the SOFC, hence a lot of attention is given to the cathodes and their interfaces. The airbrushed solution combustion (ASC) method was used to fabricate an LSM thin film on a dense YSZ substrate. A single phase LSM perovskite was obtained with very thin and interconnected porosity, and a small average grain size (55 nm). The nanostructured LSM thin film electrode showed a low total activation energy (1.27 eV) at high temperatures, but a high area specific resistance at 850°C (55 Ω.cm²). The activation energy for the dissociative adsorption and diffusion of oxygen was significantly low (1.27eV), while the charge transfer and oxygen ion migration activation energy at the LSM/YSZ interface (1.28 eV) was closer to those usually reported.The authors would like to thank Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNpQ) and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) in Brazil and Instituto de Cerámica y Vidrio (ICV) and Consejo Superior de Investigaciones Científicas (CSIC) in Spain.Peer reviewe

ANALISIS PENGARUH MOTIVASI KERJA DAN FAKTOR KOGNISI PEKERJA TERHADAP KEMAMPUAN KERJA SERTA DAMPAKNYA TERHADAP PERFORMANSI KERJA (STUDI KASUS DI PT. SANKEN INDONESIA-BEKASI)

Makalah ini bertujuan untuk memperkirakan berapa besar pengaruh yang diberikan dari variabel Motivasi Kerja dan Kognisi Pekerja terhadap Kemampuan Kerja serta dampaknya terhadap Performansi di PT. SANKEN INDONESIA dengan menggunakan analisis jalur (Path Analysis), dengan tujuan menerangkan akibat langsung dan tidak langsung seperangkat variabel sebagai variabel penyebab (eksogenus) terhadap seperangkat variabel lainnya yang merupakan variabel akibat (endogenus). Berdasarkan pengolahan data dengan menggunakan analisis jalur menunjukkan bahwa pengaruh antara variabel Motivasi Kerja dan Kognisi Pekerja terhadap Kemampuan Kerja memberikan kontribusi sebesar 38 %, sedangkan faktor lain diluar variabel penelitian yang tidak teridentifikasi oleh model penelitian dan dapat mempengaruhi peningkatan serta penurunan Kemampuan Kerja adalah sebesar 62%. Sedangkan pengaruh antara variabel Motivasi Kerja (X1), Kognisi Pekerja (X2) dan Kemampuan Kerja (Y) terhadap Performansi Kerja (Z) adalah sebesar 56%, sedangkan faktor lain diluar variabel penelitian yang tidak teridentifikasi oleh model penelitian dan dapat mempengaruhi peningkatan serta penurunan Performansi Kerja (Z) adalah sebesar 44 %. Kata Kunci : Ergonomi Industri, Analisis Jalur, Faktor Kognisi, Ergonomi Kogniti

New direct alcohol and hydrogen fuel cells for naval and aeronautical applications (PILCONAER)

In the current context of demand for reliable, low cost and low environmental impact energy sources, many countries and companies are mostly focused on fuel cells (FC) in fields as transportation and stationary power generation and portable devices. Lately, FCs have begun to be applied in naval and aeronautical systems due to its high efficiency, low noise and environmental advantages. These applications could range from propulsion systems to auxiliary power units(APU). The main problems associated with the use of FCs in these areas are the current high cost due to the materials used, i.e. Nafion and Pt, the lack of durability testing in these specific conditions, security issues to flammability and high H2 pressures and low availability as a fuel, or the toxicity of methanol used as a fuel, and specific parameters such as weight in aircraft applications and volume in marine applications. Currently it is working on each of these issues, and at this point the ethanol as direct fuel is considered crucial. The use of ethanol as fuel has the advantage of easy transportation, storage and refueling, and is nontoxic. Bioethanol is a promising energy source, produced from raw materials containing sugar or starch. These raw materials exists in all parts of the world and is renewable, which involves the use of local energy sources contributing to the diversification of energy supply, reducing import dependence, increasing security of supply and generating new opportunities for agriculture. The main objective of the project is the development of low power stacks (stacks) fed with methanol (DMFC)and ethanol (DEFC) based on the development of new catalysts and membranes. PILCONAER aims contributing to the development of a sustainable use technology, further commitment to the restoration of the natural environment and biodiversity conservation

Alternativas de bajo coste a la captura fotovoltaica

18 pp.-- Comunicación presentada en el Seminario "Soluciones para el cambio climático mediante una edificación eficiente. Gestión integral de la energía en la construcción", organizado por el Instituto de Automática Industrial (IAI-CSIC) y la Fundación Terrasol, que se celebró el día 21 de marzo de 2007 en el salón de Actos del Edificio Central del CSIC

SÍNTESIS Y CARACTERIZACIÓN DE MATERIALES CERÁMICOS Y/O METÁLICOS Y DESARROLLO DE ENSAMBLAJES DE ELECTRODO-MEMBRANA, PARA APLICACIONES ELECTROQUÍMICAS Y ELECTROCATALÍTICAS

La síntesis por combustión, método de síntesis relativamente nuevo, es la que se ha utilizado con gran éxito para preparar materiales cerámicos con estructura perovsquita y materiales metálicos, que se han podido utilizar con resultados más que prometedores como catalizadores en la oxidación parcial de metanol, así como electrocatalizadores en ánodo, en PEMFCs y DMFCs. Junto con este método de síntesis también se ha desarrollado un sistema de fabricación propia de la capa catalítica de los denominados ensamblajes electrodos-membrana (MEA), sonsiste en utilizar la aerografía automática y suspensiones con reología adecuada. Consiguiendo con este método MEAs que han dado lugar a densidades de potencia superiores a las de los ensamblajes comerciales en PMFCs teniendo en cuenta las características de los materiales para preparados por combustión, se ha utilizado la síntesis por vía cerámica convencional para conseguir materiales (Ca(Ti,Fe)O3-d) que puedan ser utilizados como membranas separadoras de gases en la denominada síntesis de gases combustibles (syngas), como es el H2 que se necesita para las pilas de Combustible.JOULE “Development of low temperature fuel cells with methanol as fuel option” JOE3-CT97-0049 FEDER “Development of materials for the polymeric fuel cell integrated prototype construction” 2FD97-1405-C02-01.Peer reviewe

Recycling of sustainable systems and substrates and its energetic use in remote zones (Vasssuren)

En: 1st Spanish National Conference on Advances in Materials Recycling and Eco – Energy Madrid, 12-13 November 2009.-- Editors: F. A. López, F. Puertas, F. J. Alguacil and A. Guerrero.-- 2 pages, 1 figure.This work deals with the development of innovative solutions to cover the energy supply in remote and depressed zones. The cost of so-called “green” energy is being reduced as its efficiency is increasing day by day, both in the electric generation through photovoltaics, wind energy or fuel cells. The aim of this work is to study, design, develop and evaluate a new integrated and self-sustained energy system, able to supply the basic electric energy to a remote and local agricultural plant. It will be integrated by photovoltaic devices used to electrically feed an electrolizer, able to obtain hydrogen from organic residues, the storage of this hydrogen will be done under pressurized tanks or by physical adsorption onto different substrates. This hydrogen will be used in a Proton Exchange Membrane Fuel Cell (PEMFC) with a power density of 5-10kW, in order to provide electricity to a local agricultural self-sustainable plant. This proposal deals also with the viability of the use of residues from the local socioeconomic base as the raw material in the electrolyzer for the hydrogen production. Therefore, generating a self-sustaining energetic system suitable for backwoods and remote areas of undeveloped countries.The authors are gratefull to the finnancial support of the following projects: UE Apollon B (NMP3-CT-033228), MICINN Mariena ENE2008-06888-C02-01/CONPeer reviewe

Membrana híbrida orgánico-inorgánico de intercambio iónico, su preparación y utilización en dispositivos electroquímicos

Membrana híbrida orgánico-inorgánico de intercambio iónico, su preparación y utilización en dispositivos electroquímicos. Membrana híbrida orgánico-inorgánico compuesta por una matriz polimérica preparada a partir de látex prevulcanizado de caucho natural y una carga inorgánica con propiedades de conductor protónico que puede actuar como separador y electrolito sólido en dispositivos electroquímicos tales como, sensores y separadores de gases, baterías o pilas de combustible. Esto les confiere unas excelentes propiedades mecánicas, sobretodo en alargamiento a la rotura, una flexibilidad muy superior a la de sus competidoras, y una inmejorable elasticidad. El proceso de producción es rápido y sencillo, no necesita ni temperaturas ni presiones elevadas, por lo que no supone un gran gasto energético. Por otra parte, no requiere el uso de ningún disolvente, por lo que no es contaminante y además es mucho mas barato.Peer reviewedConsejo Superior de Investigaciones Científicas (España)B1 Patente con informe sobre el estado de la ténic

Phase assembly and electrical conductivity of spark plasma sintered CeO2–ZrO2 ceramics

Ce x Zr1−x O2 (x = 0.10, 0.16 and 0.33) nanocrystalline powders were obtained by a two-step synthesis technique and sintered by spark plasma sintering (SPS). As consequence of the reduction of Ce4+ to Ce3+ species by carbon in the graphite environment in SPS, phase assemblies including tetragonal, monoclinic and pyrochlore phases were generated in the ceramics during the sintering process. The electrical conductivity was highly dependent on phase assembly and atmosphere (N2, H2 and O2). A significant decrease in the activation energy was noticed in the ceramics with high pyrochlore content when measuring the conductivity in H2 atmosphere, consequence of the strong reduction promoted in these ceramics during the measurement. Equal conduction behavior with similar activation energy was observed in all the ceramics when measuring in O2 atmospherePeer reviewe