Electrochemical study of platinum deposited by electron beam evaporation for application as fuel cell electrodes

Platinum is the most used catalyst in electrodes for fuel cells due to its high catalytic activity. Polymer electrolyte and direct methanol fuel cells usually include Pt as catalyst in their electrodes. In order to diminish the cost of such electrodes, different Pt deposition methods that permit lowering the metal load whilst maintaining their electroactivity, are being investigated. In this work, the behaviour of electron beam Pt (e-beam Pt) deposited electrodes for fuel cells is studied. Three different Pt loadings have been investigated. The electrochemical behaviour by cyclic voltammetry in H2SO4, HClO4 and in HClO4+MeOH before and after the Pt deposition on carbon cloth has been analysed. The Pt improves the electrochemical properties of the carbon support used. The electrochemical performance of e-beam Pt deposited electrodes was finally studied in a single direct methanol fuel cell (DMFC) and the obtained results indicate that this is a promising and adequate method to prepare fuel cell electrodes

Electrochemical study of platinum deposited by electron beam evaporation for application as fuel cell electrodes

Platinum is the most used catalyst in electrodes for fuel cells due to its high catalytic activity. Polymer electrolyte and direct methanol fuel cells usually include Pt as catalyst in their electrodes. In order to diminish the cost of such electrodes, different Pt deposition methods that permit lowering the metal load whilst maintaining their electroactivity, are being investigated. In this work, the behaviour of electron beam Pt (e-beam Pt) deposited electrodes for fuel cells is studied. Three different Pt loadings have been investigated. The electrochemical behaviour by cyclic voltammetry in H2SO4, HClO4 and in HClO4+MeOH before and after the Pt deposition on carbon cloth has been analysed. The Pt improves the electrochemical properties of the carbon support used. The electrochemical performance of e-beam Pt deposited electrodes was finally studied in a single direct methanol fuel cell (DMFC) and the obtained results indicate that this is a promising and adequate method to prepare fuel cell electrodes

Comportamiento electroquímico y en pila de combustible de cátodos fabricados mediante evaporacion electrónica de Pt frente a electrodos comerciales

(SPA) Con el objetivo de disminuir el coste de los electrodos utilizados en las pilas de combustible de membrana polimérica se ha llevado a cabo un estudio de la influencia sobre la respuesta electroquímica y en ensayos en monocelda de pila de combustible de alcohol directo, de la deposición por evaporación electrónica de platino sobre tela de carbón. Se han estudiado en las mismas condiciones dos electrodos comerciales con distinta carga de catalizador y dos electrodos preparados por evaporación electrónica de platino. Se encuentra que la evaporación electrónica de platino sobre tela de carbón ahorra carga de catalizador, aumenta la superficie electroactiva y permite alcanzar rendimientos comparables a los de los electrodos comerciales, mejorando mucho la potencia obtenida por unidad de masa de material catalítico. (ENG) In order to diminish the cost of the electrodes used in polymer membrane fuel cells a study of the influence on the electrochemical response and essays in a single direct methanol fuel cell of the deposition by electronic evaporation of Platinum on carbon cloth has been carried out. Two commercial electrodes with different catalyst loading and two electrodes prepared by electronic evaporation of Platinum have been studied in the same conditions. It can be concluded that electronic evaporation of Platinum on carbon cloth saves catalyst load, increases the electroactive surface area and reaches fuel cell performances comparable with those obtained using commercial electrodes, improving clearly the power obtained per unit mass of catalytic material

Diseño de una instalación para ensayo de pilas de combustible en condiciones atmosféricas de vuelo de un avión no tripulado

Después de estudiar la idoneidad de las pilas de combustible tipo PEM de hidrógeno y DMFC de metanol directo para su utilización en sistemas propulsivos de aeronaves no tripuladas (UAV), se procedió a simular sus respectivas curvas de polarización en condiciones de vuelo. Es importante estudiar cómo afecta al rendimiento de las pilas de combustible la variación de las condiciones atmosféricas durante el vuelo de un UAV, dado que la mayor parte de los sistemas comerciales están concebidos para su uso en tierra. Por tanto, es de interés la validación de esos modelos de simulación a partir de datos experimentales. Para ello, se presenta en este trabajo el diseño de un banco experimental climatizado de pilas de combustible, en el que poder variar magnitudes como la presión atmosférica, la temperatura o la humedad relativa. Permitirá elegir los casos simulados de mayor interés típicos de la envolvente de vuelo de distintos tipos de UAV en función de las características de la instalación. El banco consiste en una cámara climática estanca y aislada térmicamente a la que van conectados un circuito de refrigeración con intercambiador de calor y una bomba de vacío. En una segunda fase se incluirá un evaporador para el estudio de la humedad relativa. Se elige control PID mediante sonda PT100 y sensores de presión y humedad. El diseño permite condiciones suficientes de estabilidad geométrica y temporal en el interior de la cámara como para estudiar los casos elegidos. Estudios previos similares, se centran en pilas de combustible alimentadas con hidrógeno. En este caso se pueden estudiar también pilas de combustible de metanol, para la que ya existen ejemplos de UAV

Perspectives on the design and use of direct alcohol fuel cells fed by alcohol blends

The fast-growing power demand by portable electronic devices has promoted the increase of global production of portable PEM fuel cell, a quarter of them consist of direct methanol fuel cell (DMFC) units. These present the advantage of being fuelled directly with a liquid fuel, as well as direct ethanol fuel cells (DEFC) do

Polipirrol, un buen soporte para electrodos de pilas de combustible de metanol directo (DMFC)

(SPA) El polipirrol es uno de los polímeros conductores más utilizados en la preparación de electrodos debido a su alta actividad catalítica para la oxidación y reducción del metanol. En este trabajo se ha depositado electroquímicamente polipirrol a diferentes potenciales de depósito, Ed, sobre tela de carbón no tejida Freudenberg en medio ácido. Se ha analizado la morfología y la respuesta electroquímica en medio HClO4 y en presencia de HClO4+MeOH antes y después de la síntesis del polipirrol sobre ella. Lastructura de las películas obtenidas se ha estudiado por espectroscopia infrarroja de transformada de Fourier, FTIR. Se observa que el polipirrol mejora las propiedades electroquímicas de la tela de carbón, obteniéndose el mejor resultado para su aplicación como soporte del catalizador en pilas de combustible con la película sintetizada a 1,0V. (ENG) Polypyrrole is one of the most used conducting polymers in electrode building due to its high catalytic activity to the methanol oxidation and reduction. By this motive, polypyrrole has been electrochemically synthesized at constant potential, Ed, on Freudenberg carbon cloth in acid medium. Carbon cloth morphology and electrochemical behaviour in HClO4 and in HClO4+MeOH before and after the polypyrrole eposition have been analysed. The structure of the films was studied by Fourier transform infrared spectroscopy, FTIR. The polypyrrole improves the electrochemical properties of the studied carbon cloth. The biggest charge of the electroactive area is the one synthesized at 1.0V, being the best for its application as catalyst support in fuel cells

Contribution sharing of a fuel mixture components to the fuel cell potencial of a direct alcohol fuel cell

The increasing worldwide demand for electricity impels to develop clean and renewable energy resources. In the field of portable power devices not only size and weight represent important aspects to take into account, but the fuel and its storage are also critical issues to consider. In this last sense, the direct methanol (MeOH) fuel cells (DMFC) play an important role as they can offer high power and energy density, low emissions, ambient operating conditions and fast and convenient refuelling

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

Asociaciones de crustáceos decápodos de volcanes de fango y fondos adyacentes en aguas españolas del Golfo de Cádiz

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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