Nanoenergy Flavio Leandro de Souza Edson Roberto Leite Editors Nanoenergy Nanotechnology Applied for Energy Production 123 Editors Flavio Leandro de Souza Edson Roberto Leite Centro de Ciências Naturais e Humanas CCET, Depart. de Química Universidade Federal do ABC Universidade Federal de Sao Carlos Santo André São Carlos, SP Brazil Brazil ISBN 978-3-642-31735-4 ISBN 978-3-642-31736-1 (eBook) DOI 10.1007/978-3-642-31736-1 Springer Heidelberg New York Dordrecht London Library of Congress Control Number: 2012944973 Ó Springer-Verlag Berlin Heidelberg 2013 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work.
Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc.
in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.com) Preface Today, the world urgently needs alternative sources of environmentally sustainable energy supply for rapid industrial development and for consumption, such as in China.
Indeed, it has become crucial for the future of humanity to find clean and safe methodologies to produce alternative energy for avoiding the growing global warming effect and urban air pollution. As a consequence, to reach this purpose it is necessarily to create new materials to build devices for renewable energy. In the past decade, funding agencies and governmental programs were created worldwide to give the scientific community support to find and develop new materials and devices for alternative energy production. In this context, this book tries to give an overview of the main developments in Brazil and its contribution to produce a clean and alternative source of energy.
This book written by leading experts in major fields of physics, chemistry, and material sciences in Brazil covers the fundamental use of semiconductors, organic, and inorganic materials to build devices that directly convert solar irradiation into hydrogen and electricity, the latest development of biofuel cell and low temperature fuel cell devices using nanomaterials, as well as the latest advances on lithium-ion batteries and nickel– metal hydride batteries. This book consists of seven chapters which address in detail the fundamental importance of nanomaterials on the device performance and efficiency. The first three chapters concern an overview of the main contribution of research in development of a photoelectrochemical device which directly converts solar irradiation into electricity and hydrogen. This book begins with a chapter by Nogueira and Freitas summarizing the recent progress on the incorporation of inorganic semiconductor nanoparticles and metal nanoparticles into organic solar cells.
The improvement caused by nanoparticles insertion on organic solar cell and its efficiency are discussed. 2, Souza and Polo describe the recent advances in the developments on tris-heteroleptic ruthenium dye-sensitizers and its impact on dye-sensitized solar cells, efficiency. In addition, this chapter also gives an overview of natural dyes promptly obtained from several fruits or flowers in a very simple way which are also being employed as semiconductor sensitizers to produce these devices at a low cost. Souza and Leite present the recent advances on chemical synthesis to obtain a very promising semiconductor to be used as v vi Preface photoanode in a photoelectrochemical device.
This chapter illustrates a general discussion on solid–liquid interface, photoelectrochemical device performance due to a variety of nanostructured morphologies prepared by chemical methods and the main features of molecular oxygen evolution mechanism (OER) from water oxi- dation under solar light irradiation. The next two chapters give readers the recent progress and fundamental dis- cussion on producing an efficient fuel cell working at low temperature based on nanomaterials and interface of biomolecule immobilized on nanostructure surface. Olyveira and Crespilho describe in this chapter recent studies using biological materials immobilized on nanostructured film surface to generate electricity. The main focus of this chapter is how to build biofuel cells with high power density, controlling the enzyme immobilization methodologies and stability.
Lima and Cantane present a development of a new class of electrocatalysts for application on low temperature fuel cells. This chapter discusses the main challenges of oxygen reduction reaction (ORR), and of the ethanol oxidation reaction (EOR) for proton and anion exchange membrane electrolytes. Also, the performance and test sta- bility for some ORR electrocatalysts are included. Finally, the last two chapters are dedicated to contextualize the readers on the advances in development of lithium-ion batteries and nickel–metal hydride bat- teries with the use of nanomaterials.
Huguenin and Torresi describe the main advances resulting from the use of sol–gel route to produce V2O5 xerogel, nano- composites of V2O5, and polymer cathodes for lithium-ion batteries. This chapter reviews the importance of structural features for better understanding of lithium- ion insertion/deinsertion, and their influence on electrochemical properties and charge capacity. Also, the use of nanomaterial on lithium-ion batteries is dis- cussed. A chapter focusing on novel hydrogen storage materials and fundamental aspects for using nickel–metal hydride (Ni–MH) as rechargeable batteries is dis- cussed by Santos and Ticianelli.
The recent progress on developments of anode materials, with special emphasis on the nanostructured Mg alloys, its challenges, and perspectives are reviewed. We are thankful to our current authors for their valuable contribution. We hope that this book gives an important contribution for understanding the urgency of the world to develop a new and efficient device for supplying the current necessity of humanity to have a clean and sustainable source of energy. In addition, our expectations to aid a wide scientific community to understand the actual progress was only possible due to consolidation of nanoscience and nanotechnology.
Santo André, Brazil, May 2012 Prof. Flavio Leandro de Souza Prof. Edson Roberto Leite Contents Incorporation of Inorganic Nanoparticles into Bulk Heterojunction Organic Solar Cells. de Freitas and Ana Flávia Nogueira Nanomaterials for Solar Energy Conversion: Dye-Sensitized Solar Cells Based on Ruthenium (II) Tris-Heteroleptic Compounds or Natural Dyes.
49 Juliana dos Santos de Souza, Leilane Oliveira Martins de Andrade and André Sarto Polo Facile Routes to Produce Hematite Film for Hydrogen Generation from Photoelectro-Chemical Water Splitting. de Souza, Allan M. de Carvalho, Ricardo H. Gonçalves and Edson R.
Leite Biofuel Cells: Bioelectrochemistry Applied to the Generation of Green Electricity. Luz and Frank N. Crespilho Recent Advances on Nanostructured Electrocatalysts for Oxygen Electro-Reduction and Ethanol Electro-Oxidation. Lima and Daniel A.
Cantane Nanocomposites from V2O5 and Lithium Ion Batteries. 153 Fritz Huguenin, Ana Rita Martins and Roberto Manuel Torresi Magnesium Alloys as Anode Materials for Ni-MH Batteries: Challenges and Opportunities for Nanotechnology. 179 Sydney Ferreira Santos, Flavio Ryoichi Nikkuni and Edson Antonio Ticianelli vii Incorporation of Inorganic Nanoparticles into Bulk Heterojunction Organic Solar Cells Jilian N. de Freitas and Ana Flávia Nogueira Abstract Organic solar cells are among the most promising devices for cheap solar energy conversion.
The classical device consists of a bulk heterojunction of a conjugated polymer/fullerene network. Many research groups have focused on the replacement of the fullerene derivative with other materials, especially inorganic nanoparticles, due to their easily tunable properties, such as size/shape, absorption/ emission and charge carrier transport. In this chapter, we highlight recent progress on the incorporation of inorganic semiconductor nanoparticles and metal nanoparticles into organic solar cells. The role of these nanoparticles in the improvement of photocurrent, voltage and efficiency is discussed.
1 Introduction There is a continuously growing demand for clean and renewable energy, impelled by the need of bringing electricity to remote areas and due to an increase in world’s population, which requires more (and safer) energy, at the same time minimizing the impacts on Earth and nature. Solar energy is considered a promising alternative to fulfill these aims. For many decades the photovoltaic industry has been dominated by solid-state devices based mainly on silicon [1]. The energy conversion efficiency of the best J.
Box 6154 Campinas-SP 13083-970, Brazil e-mail: jfreitas@gmail. Nogueira e-mail: anaflavia@iqm. de Souza and E.1007/978-3-642-31736-1_1, Springer-Verlag Berlin Heidelberg 2013 2 J. de Freitas and A.
Nogueira monocrystalline Si photovoltaic cells is *25 % [2, 3], which is very close to its theoretical limit of 31 % [4]. However, the manufacturing of Si-based devices is very expensive due to the requirements for high purity crystalline semiconductor substrates [5]. Such drawbacks results in the high cost associated with solar energy exploration [6]. In order to increase the share of photovoltaic technology, espe- cially considering the application of devices in low-scale consumer goods, such as cells phones, laptops, energetic bags and clothes, etc., the development of low-cost devices is extremely necessary.
In this scenario, organic solar cells (OSC) appear as very interesting candidates. Since these devices are usually assembled with organic semiconductors, either small molecules or polymers, they show great promise due to the synthetic vari- ability of organic materials, their low-temperature of processing (similar to that applied to common plastics), and the possibility of producing lightweight, flexible, easily manufactured and inexpensive solar cells. Moreover, the high optical absorption coefficients of conducting polymers, in comparison to silicon, provide the possibility of preparation very thin (100–200 nm) solar cells. Recent progress in the field of OSC has led to a device with the maximum efficiency of 7.
In order to further enhance the competitiveness of OSC with other technologies, efficiency and long term stability remain crucial issues. The photocurrent in these solar cells is limited by the light-harvesting capability of the individual molecules or polymers in the device. The synthesis of new low band gap polymers has been intensively studied for the purpose of overcoming this drawback [8], but it is a complicated matter since changing the band gap energy usually changes the energetic value of the highest occupied molecular orbital (HOMO), which have unfavourable implications on the open circuit voltage. Morphology is also important in this context since it impacts directly on charge transport, and an intimate contact between donor and acceptor materials on a nanoscale range is difficult to achieve due to phase separation.
A better under- standing of the processes at the nanoscale level, particularly those in layer-to-layer interfaces, is needed, and the exact role of phase separation remains the subject of active research. To overcome some of these drawbacks, different types of acceptor materials have been applied in the photoactive layer of OSC, such as carbon nanotubes and inorganic semiconductor nanoparticles. When at least one component is replaced by an inorganic counterpart, these devices are referred to as hybrid solar cells (HSC). Figure 1 shows the structure and dimensions of nanomaterials typically used in OSC and HSC.
The use of inorganic nanoparticles in optoelectronic devices has some advan- tages, mainly related to the versatility of these materials, which often can be easily synthesized in a great variety of sizes and shapes, according to the desired prop- erties. Usually, the so-called inorganic ‘‘nanoparticles’’ are structures that present at least one dimension between 1 and 100 nm.