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Diamond in nanoparticle form is a promising material that can be used as a robust and chemically stable catalyst support in fuel cells. It has been studied and characterized physically and electrochemically, in its thin film and powder forms, as reported in the literature. In the present work, the electrochemical properties of undoped and boron-doped diamond nanoparticle electrodes, fabricated using the ink-paste method, were investigated. Methanol oxidation experiments were carried out in both half-cell and full fuel cell modes. Platinum and ruthenium nanoparticles were chemically deposited on undoped and boron doped diamond nanoparticles through the use of NaBH(4) as reducing agent and sodium dodecyl benzene sulfonate (SDBS) as a surfactant. Before and after the reduction process, samples were characterized by electron microscopy and spectroscopic techniques. The ink-paste method was also used to prepare the membrane electrode assembly with Pt and Pt-Ru modified undoped and boron-doped diamond nanoparticle catalytic systems, to perform the electrochemical experiments in a direct methanol fuel cell system. The results obtained demonstrate that diamond supported catalyst nanomaterials are promising for methanol fuel cells.

No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work.Cover design: eStudio Calamar S.L.Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) PrefaceEnergy is the lifeblood of civilization. Access to relatively inexpensive and plentiful energy has been and will continue to be its driving force. In the past few years, the reality of the fragile nature of an oil dominated energy infrastructure has become apparent. Civilization is engaged in a life and death struggle to redefine its primary energy resources and to find transitional solutions without invoking chaos. Time is relatively short and it will be in the hands of the current generation of students to solve.The authors began working on Energy Resources and Systems in 1996. The goal of the authors was to provide a comprehensive series of texts on the interlinking of the nature of energy resources, the systems that utilize them, the environmental effects, the socioeconomic impact, the political aspects and governing policies. Volume 1 on Fundamentals and Non Renewable Resources was published in 2009. It blends fundamental concepts with an understanding of the non-renewable resources that dominate today's society.The second volume of Energy Resources and Systems is focused on renewable energy resources. Renewable energy mainly comes from wind, solar, hydropower, geothermal, ocean, bioenergy, ethanol and hydrogen. Each of these energy resources is important and growing. For example, high-head hydroelectric energy is a well established energy resource and already contributes about 20% of the world's electricity. Some countries have significant high-head resources and produce the bulk of their electrical power by this method (e.g., Norway-over 98%, Paraguay-100% and Brazil-85%). However, the bulk of the world's high-head hydroelectric resources have not been exploited, particularly by the underdeveloped countries. Low-head hydroelectric is unexploited and has the potential to be a growth area. Wind energy is the fastest growing of the renewable energy resources for the electricity generation. Solar energy is a popular renewable energy resource. About 89 10 15 watt (W) of solar energy is absorbed annually by the earth's land mass and oceans. However, this only translates to around 1,000 W m 2 spread over the earth's surface area. The diffuse nature of solar energy has limited its growth because it is difficult to base systems on resources with a low energy density. Geothermal energy is viable near volcanic areas. Iceland for example has taken advantage of its geothermal resources in that it produces 24% of its electricity and heats 87% of its buildings with it. Bioenergy and...

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Diffusion of boron, lithium, nitrogen, oxygen, and hydrogen into type IIa natural diamond was studied. The diffusion was performed in two steps. First, diffusion of Li and oxygen was performed in nitrogen atmosphere at 860 °C for one hour. The sample was then placed in a hot filament chemical vapor deposition (CVD) growth reactor and diffusion was performed for two hours in hydrogen atmosphere from a boron solid source placed on the surface of the sample. The condition of diffusion were those used routinely during CVD growth. After diffusion, the concentration of Li was of the order of 2×1016 cm−3 at the depth of 0.5 micrometer, and oxygen, nitrogen, and boron were found to be in the range (1–4)×1020 cm−3 at the same depth. The diffusion of hydrogen under conditions specific to CVD growth has also been studied for the first time and was found to be quite strong.