Nanocatalysis E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 1331

Veröffentlichungsjahr: 2013

Beschreibung

Exhibiting both homogeneous and heterogeneous catalytic properties, nanocatalysts allow for rapid and selective chemical transformations, with the benefits of excellent product yield and ease of catalyst separation and recovery. This book reviews the catalytic performance and the synthesis and characterization of nanocatalysts, examining the current state of the art and pointing the way towards new avenues of research. Moreover, the authors discuss new and emerging applications of nanocatalysts and nanocatalysis, from pharmaceuticals to fine chemicals to renewable energy to biotransformations.

Nanocatalysis features contributions from leading research groups around the world. These contributions reflect a thorough review of the current literature as well as the authors’ first-hand experience designing and synthesizing nanocatalysts and developing new applications for them. The book’s nineteen chapters offer a broad perspective, covering:

• Nanocatalysis for carbon-carbon and carbon-heteroatom coupling reactions
• Nanocatalysis for various organic transformations in fine chemical synthesis
• Nanocatalysis for oxidation, hydrogenation, and other related reactions
• Nanomaterial-based photocatalysis and biocatalysis
• Nanocatalysts to produce non-conventional energy such as hydrogen and biofuels
• Nanocatalysts and nano-biocatalysts in the chemical industry

Readers will also learn about the latest spectroscopic and microscopy tools used in advanced characterization methods that shed new light on nanocatalysts and nanocatalysis. Moreover, the authors offer expert advice to help readers develop strategies to improve catalytic performance.

Summarizing and reviewing all the most important advances in nanocatalysis over the last two decades, this book explains the many advantages of nanocatalysts over conventional homogeneous and heterogeneous catalysts, providing the information and guidance needed for designing green, sustainable catalytic processes.

Leseprobe

Contents

Cover

Title Page

Copyright

Foreword

Preface

List of Contributors

Chapter 1: Introduction to Nanocatalysis

WHAT IS NANOCATALYSIS?

NANOCATALYSIS: TRUTH OR HYPE?

REFERENCES

Chapter 2: Nanocatalysts for the Heck Coupling Reactions

INTRODUCTION

HETEROGENEOUS CATALYSTS FOR THE HECK REACTION

SYNTHETIC METHODS TO CATALYSTS FOR THE HECK COUPLING

NANOPARTICLES FOR THE HECK COUPLING REACTION

CORE–SHELL NANOPARTICLES FOR THE HECK COUPLING REACTION

MESOPOROUS MATERIALS FOR THE HECK COUPLING REACTIONS

POLYMERIC-BASED NANOCATALYSTS FOR THE HECK COUPLING REACTIONS

CARBON NANOMATERIAL-SUPPORTED HECK COUPLING REACTIONS

REFERENCES

Chapter 3: Nanocatalysts for The Suzuki Coupling Reactions

SUZUKI COUPLING REACTION

FROM HOMOGENEOUS TO NANOPARTICLE CATALYSTS

NANOPARTICLE ACTIVITY IN SUZUKI C—C COUPLING REACTION

STABILITY AND REUSABILITY OF NANOCATALYSTS

INSIGHT ON MECHANISTIC ASPECTS

ACTIVE Pd-NPs AND OTHER METAL NPs FOR SUZUKI C—C COUPLING

SUMMARY AND FUTURE OUTLOOK

REPRESENTATIVE EXPERIMENTAL PROCEDURES

REFERENCES

Chapter 4: Sonogashira Reactions Using Nanocatalysts

INTRODUCTION

CATALYTIC ACTIVITY, STABILITY, AND REUSABILITY

MECHANISTIC ASPECTS

SUMMARY AND FUTURE OUTLOOK

REPRESENTATIVE EXPERIMENTAL PROCEDURES

REFERENCES

Chapter 5: Nanocatalysts for Hiyama, Stille, Kumada, and Negishi C–C Coupling Reactions

INTRODUCTION

CATALYTIC NANOPARTICLES FOR C—C CROSS-COUPLINGS

HIYAMA COUPLING

NEGISHI COUPLING

STILLE COUPLING

KUMADA–CORRIU COUPLING

MECHANISMS

OUTLOOK

CONCLUSIONS

REFERENCES

Chapter 6: Aryl Carbon–Heteroatom Coupling Reactions Using Nanometal Catalyst

INTRODUCTION

METAL NANOPARTICLE-CATALYZED ARYL–SULFUR BOND FORMATION

METAL NANOPARTICLE-CATALYZED ARYL–NITROGEN BOND FORMATION

METAL NANOPARTICLE-CATALYZED ARYL–OXYGEN BOND FORMATION

METAL NANOPARTICLE-CATALYZED ARYL–SELENIUM BOND FORMATION

MISCELLANEOUS C—N BOND FORMATION REACTIONS CATALYZED BY METAL NANOPARTICLES

CONCLUSION

REFERENCES

Chapter 7: Nanostructured Catalysts for the Aldol, Knoevenagel, and Henry Reactions

INTRODUCTION

RECENT PROGRESS ON NANOPARTICLE-BASED HETEROGENEOUS CATALYSTS FOR THE ALDOL, KNOEVENAGEL, AND HENRY REACTIONS

MESOPOROUS SILICA-SUPPORTED CATALYSTS FOR THE ALDOL, HENRY, AND KNOEVENAGEL REACTIONS

POLYMERIC-BASED NANOCATALYSTS FOR THE HENRY COUPLING REACTIONS

REFERENCES

Chapter 8: Nanocatalysts for Rearrangement Reactions

INTRODUCTION

SYNTHESIS AND CHARACTERIZATION OF NANOCATALYSTS

CATALYTIC ACTIVITY, STABILITY, AND REUSABILITY

INSIGHT ON MECHANISTIC ASPECTS

SUMMARY AND FUTURE OUTLOOK

REPRESENTATIVE EXPERIMENTAL PROCEDURES

ACKNOWLEDGMENTS

REFERENCES

Chapter 9: Oxidation of Alcohols Using Nanocatalysts

INTRODUCTION

RUTHENIUM-CATALYZED ALCOHOL OXIDATION

PALLADIUM-CATALYZED ALCOHOL OXIDATION

AU-CATALYZED ALCOHOL OXIDATION

BIMETALLIC NANOPARTICLE-CATALYZED ALCOHOL OXIDATION

SUMMARY AND FUTURE OUTLOOK

REFERENCES

Chapter 10: Tuning the Morphology of Metal Oxides for Catalytic Applications

INTRODUCTION

COBALT OXIDES

FERRIC OXIDES

CERIUM DIOXIDE

CONCLUDING REMARKS

REFERENCES

Chapter 11: Nanocatalysts for Hydrogenation Reactions

INTRODUCTION

HYDROGENATION OF VARIOUS UNSATURATED COMPOUNDS

CONCLUSIONS

REFERENCES

Chapter 12: Hydrogenolysis Reactions Using Nanocatalysts

NANOCATALYSIS FOR GLYCEROL HYDROGENOLYSIS

NANOCATALYSIS FOR ALKANE HYDROGENOLYSIS

REPRESENTATIVE EXPERIMENTAL DETAILS

REFERENCES

Chapter 13: Nanomaterial-Based Photocatalysts

INTRODUCTION

HISTORICAL PERSPECTIVES IN PHOTOCATALYSIS

CURRENT STATE OF PHOTOCATALYSIS (FROM 2000 TO NOW)

MECHANISTIC DETAILS

USE OF VISIBLE LIGHT

SYNTHETIC METHODS

FUTURE DIRECTIONS

CONCLUDING REMARKS

REFERENCES

Chapter 14: Nanocatalysts for Water Splitting

INTRODUCTION

KNOWLEDGE ON PHOTOCATALYTIC WATER SPLITTING

ELEMENTS CONSTRUCTING SEMICONDUCTOR PHOTOCATALYSTS

UV-RESPONSIVE SEMICONDUCTOR NANOCATALYSTS FOR WATER SPLITTING

VISIBLE LIGHT-RESPONSIVE SEMICONDUCTOR NANOCATALYSTS FOR WATER SPLITTING

SUMMARY AND FUTURE PERSPECTIVE

REFERENCES

Chapter 15: Properties of Nanocatalytic Materials for Hydrogen Production from Renewable Resources

INTRODUCTION

BIOMASS GASIFICATION

STEAM REFORMING OF FAST PYROLYSIS BIO-OILS

SUGAR CONVERSION TO HYDROGEN

OVERALL H2 PRODUCTION PROCESS FROM RENEWABLE RESOURCES

X-RAY ABSORPTION SPECTROSCOPY

CONCLUSIONS

ACKNOWLEDGMENT

REFERENCES

Chapter 16: Nanocatalysts for Biofuels

INTRODUCTION

NANOCATALYSTS IN THE PRODUCTION OF LIQUID FUELS FROM BIOMASS

NANOPARTICLES AND THE BIOREFINERY: PROSPECTS AND OUTLOOK

REFERENCES

Chapter 17: Nanomaterial-Based Biocatalyst

INTRODUCTION

SYNTHESIS AND CHARACTERIZATION OF NANOMATERIAL-BASED BIOCATALYSTS

CATALYTIC ACTIVITY, STABILITY, AND REUSABILITY: ENHANCEMENT OF ENZYME FUNCTIONS VIA NANOMATERIAL-BASED BIOCATALYSTS

APPLICATIONS OF NANOMATERIAL-BASED BIOCATALYSIS

SUMMARY AND FUTURE OUTLOOK

REPRESENTATIVE EXPERIMENTAL PROCEDURES

REFERENCES

Chapter 18: Role of Nanocatalysis in Chemical Industry

INTRODUCTION

CASE STUDY 1: APPLICATION OF COLLOIDAL NANOMETAL IN CATALYSIS

CASE STUDY 2: SOLID MIXED NANOMETAL OXIDE AS REUSABLE HETEROGENEOUS CATALYST FOR PRODUCTION OF FATTY ACID ALKYL ESTERS

CASE STUDY 3: HETEROGENEOUS CATALYTIC APPLICATIONS OF “STRIPED” NANOPARTICLES

SUMMARY AND FUTURE OUTLOOK

ACKNOWLEDGMENTS

REFERENCES

Chapter 19: Nanocatalysis: Activation of Small Molecules and Conversion into Useful Feedstock

INTRODUCTION

CO OXIDATION ON AU/METAL OXIDE CATALYSTS

DIRECT SYNTHESIS OF H2O2 FROM H2 AND O2

METHANOL SYNTHESIS FROM CO AND CO2

SUMMARY AND OUTLOOK

REFERENCES

Index

Cover Design: John Wiley & Sons, Inc. Cover Illustration: © Vivek Polshettiwar

Copyright © 2013 by John Wiley & Sons, Inc. All rights reserved.

Published by John Wiley & Sons, Inc., Hoboken, New Jersey. Published simultaneously in Canada.

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Library of Congress Cataloging-in-Publication Data:

Nanocatalysis : synthesis and applications / edited by Vivek Polshettiwar, Tewodros Asefa. pages cm “Published simultaneously in Canada”–Title page verso. Includes bibliographical references and index. ISBN 978-1-118-14886-0 (cloth) 1. Nanostructured materials. 2. Catalysts. 3. Nanostructured materials–Industrial applications. 4. Catalysts–Industrial applications. I. Polshettiwar, Vivek II. Asefa, Tewodros. TA418.9.N35N2466 2013 660′.2995–dc23 2012049879

FOREWORD

This book, entitled Nanocatalysis: Synthesis and Applications, edited by Vivek Polshettiwar and Tewodros Asefa, who are both active researchers in this exciting field, comprises a broad range of authorative sections that are authored by world-class researchers. The book is an important addition to the rapidly growing area of nanocatalysis. The book gives comprehensive perspectives on a wide array or research topics related to nanocatalysis, by highlighting the importance of nanocatalysis in areas ranging from the efficient production of commodity and value-added chemical products to renewable energy and environmental remediation—topics that are of contemporary interest worldwide from government and industry to academia as well as to society as a whole. The book comprises several different topics related to nanocatalysis with topical areas distributed throughout the text, including fundamental aspects of nanocatalysis, surface science, and mechanistic and theoretical studies on how nanocatalysts function. In addition, the range of applications of nanocatalysis in several areas is also covered, including energy and environment. Therefore, researchers in both industry and academia alike, as well as new students and seasoned researchers, will appreciate reading the book.

The timing of this book could not be any better—as can be witnessed by the large number of research publications being reported in the journals concerned with nanoscience and nanotechnology in general, which relate to nanocatalysis in particular. The field of nanocatalysis has attracted intense interest over the last two decades, although, of course, the use of nano-sized materials as catalysts has been a research topic for many decades. The strength of this book is that it brings together the key areas in this broad subject in an easily accessible way. Readers will readily be able to obtain quick information on a variety of topics from synthesis and characterization of nanocatalysts as well as their applications. So, we should thank the two editors for embarking on this project and bringing together this key collection of studies on nanocatalysis. As an active researcher in the field of nanocatalysis, I strongly feel that this book will also stimulate new cutting-edge research activities in the area. However, at the same time, this book gives a wealth of fundamental information that is highly relevant for newcomers to the field as well as providing basic information to graduate and undergraduate students alike. I also consider that the text will be a valuable resource to lecturers with interests in teaching the principles of nanocatalysis. Moreover, I expect the book to inspire more researchers to work on a variety of new research aspects related to nanocatalysis and the development of novel and improved nanocatalysts, especially directed to many of the contemporary grand challenges of our generation that the world faces today in areas such as renewable energy, production of value-added chemical products, and synthesis of materials in a “greener” or sustainable way, as well as environmental remediation. The book is, therefore, a very valuable resource.

Professor Graham J. Hutchings FRS Director of the Cardiff Catalysis InstituteThe Cardiff School of ChemistryCardiff University, UK

PREFACE

Catalysis lies at the heart of chemical processes that lead to a variety of chemical products and synthetic materials. This can be highlighted by the fact that about more than 80–85% of synthetic materials and commercial chemical products see at least one, if not more, catalyst at some point of their synthesis. This means, the synthesis of many useful household products, such as medicines, detergents, polymeric fibers, perfumes, fuels, paints, lubricants, and a myriad of other value-added chemical products essential to humans, would have been neither possible nor feasible in the absence of catalysts.

Catalysts are chemical substances that enable the (“smooth”) transformation of fine chemicals into value-added chemical products or synthetic materials. Catalysts play major roles in such conversions of many different chemical species into important final products by enabling the chemical transformations to take place effectively, that is, in an economical manner, with less by-products, with less energy consumption, or by giving the desired products in larger amount in relatively shorter reaction times.

Besides many conventional chemical processes where catalysts have already been used, the emergence of the grand challenges in areas such as renewable energy and environmental problems that our world faces has made the development of catalysts capable of contributing to the production of renewable energy and environmental remediation among the “holly-grail” research areas worldwide currently. Furthermore, in the face of dwindling fossil fuel sources, the development of catalysts that allow the transformation of CO2 into fuels and the conversion of water into H2 in a viable manner has become very vital and contemporary research area today.

Catalysts are traditionally divided into two major groups based on the type of phase of the catalyst is in relative to the catalytic reaction mixtures, that is, homogeneous or heterogeneous catalysts. Homogeneous catalysts are those that exist in the same phase as the reactants. They are generally soluble organic or organometallic complexes and often give chemo-, regio-, and stereoselective products. However, they are relatively difficult to separate from reaction mixtures for reuse at the end of reactions. On the other hand, there are solid or insoluble catalysts, also called heterogeneous catalysts. In many instances, the solid catalysts contain homogeneous catalysts supported on neutral or catalytic-active solid support materials such as porous silica or alumina. These types of catalysts are easily separable and reusable at the end of reactions; however, they often give relatively poor reaction yields, compared with many of their homogeneous counterparts.

The fields of nanoscience and nanotechnology have been unquestionably thriving over the last two or so decades. The positive societal impacts of nanoscience and nanotechnology have also now become clear to scientists and engineers alike, and even to the public, although much work still remains in understanding the potential biological and health effects of many nanomaterials. One of the first examples where the applications of nanoscience and nanotechnology were successfully demonstrated has been in the area of catalysis; that is, nanoscience and nanotechnology has made it possible for a class of nanomaterials with potential applications in catalysis (or nanocatalysts) to come alight. Many nanomaterials with different interesting catalytic properties have actually been documented, and some of them have also been commercially used. In fact, even before systematic research on nanocatalyst development began or unbeknownst to many, several materials with nanoscale sizes have been successfully used as catalysts in many reactions. Nanocatalysts are interesting from a point of view of being in between homogeneous and heterogeneous catalysts, although this classification is not quite strict. In other words, nanocatalysts exhibit quasihomogeneous or quasiheterogeneous catalytic properties, and thus allow for rapid and selective chemical transformations, with excellent product yield and ease of catalyst separation and recovery. Nanocatalysis can thus be simply defined as the use of nanoscale materials in catalysis, often with effective catalytic properties, that is, efficient catalytic activities as well as ease of catalyst separation, recovery, and reuse.

The objective of the book is to review the development and progress of nanocatalysts and nanocatalysis over the past two decades and to provide readers with well-compiled information about the status of the field on the synthesis and applications of various nanocatalysts for the production of industrially and pharmaceutically important compounds and synthetic materials. The book is also prepared to give quick and highly compiled information on various topics related to nanocatalysts and nanocatalysis to students, faculty, and industrial personnel, who are working in catalysis research. This, in turn, is expected to promote further advances in the field.

The information in the book has been compiled in 19 chapters. The first chapter provides some introduction on nanocatalysts and nanocatalysis. The next six chapters are devoted to nanocatalysts or nanocatalysis for carbon–carbon and carbon–heteroatom coupling reactions. The next two chapters are devoted to nanocatalysts and nanocatalysis for fine chemical synthesis. The subsequent four chapters are devoted to the use of nanocatalysts for oxidation–hydrogenation-type reactions. The four next chapters are also devoted to the topic of nanomaterial-based photocatalysis and the use of nanocatalysis to produce nonconventional sources of energy. The last two chapters focus on the use of nanocatalysts in the chemical industry.

Many of the chapters are written in such a way that they dwell on the synthesis and characterization of nanocatalysts and their properties and applications in synthesis. Each chapter has been contributed by different groups of researchers worldwide, who have expertise in various aspects of nanocatalysts and/or nanocatalysis. Each team has used recent literature in its respective areas of expertise. Thus, we hope that the book will give a broad perspective on the design and synthetic methods to various types of nanocatalysts and their applications. In addition, the various types of advanced characterization methods described in most of the chapters will highlight the current state-of-the-art of various spectroscopic and microscopy tools used for elucidation of nanocatalysts and nanocatalysis. Moreover, methods used for probing the activities of catalysts and the strategies utilized to improve the catalytic activities and selectivities of nanocatalysts should give further information for the researchers working in the area.

We edited this book because we realize that there are several missing areas of interest in the field of nanocatalysis today, especially in light of the rapid progress being made in the field and the enormous number of papers being published in the area. In addition, although there are few other books written on topics related to nanocatalysis, this book focuses on nanocatalysts and contains a comprehensive review and a fair distribution of synthesis and characterization of nanocatalysts and application of nanocatalysts and nanocatalysis in areas ranging from pharmaceutical products to renewable energy materials and biotransformations.

The book is possible only because of the involvement of many outstanding researchers worldwide, who devoted a significant amount of their time to make contributions to the different sections of the chapters in the book. They are the real craftsmen of this very comprehensive book. We are, therefore, indebted to all of them, who have contributed enormously to make this book possible. We also acknowledge the support we have received from our coworkers, friends, and family members throughout the process of putting the book together.

Vivek Polshettiwar and Tewodros Asefa

LIST OF CONTRIBUTORS

Editors

Vivek Polshettiwar, Nanocatalysis Laboratory, Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India

Tewodros Asefa, Department of Chemistry and Chemical Biology and Department of Chemical and Biochemical Engineering, The Rutgers Catalysis Research Center (RCRC), Rutgers, The State University of New Jersey, Piscataway, NJ, USA

Authors

Abhinandan Banerjee, Department of Chemistry, University of Saskatchewan, Saskatoon, SK, Canada

A. V. Biradar, Department of Chemistry and Chemical Biology and Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, USA

Vitaliy Budarin, Department of Chemistry, Green Chemistry Centre of Excellence, University of York, Heslington, York, UK

Victorio Cadierno, Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, Oviedo, Spain

Jeong Ho Chang, Korea Institute of Ceramic Engineering and Technology, Seoul, South Korea

Rafael Chinchilla, Department of Organic Chemistry and Institute of Organic Synthesis, University of Alicante, Alicante, Spain

James H. Clark, Department of Chemistry, Green Chemistry Centre of Excellence, University of York, Heslington, York, UK

Natalia J. S. Costa, Laboratory of Nanomaterials and Catalysis, Institute of Chemistry, USP, São Paulo, Brazil

S. Das, Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA

Aziz Fihri, Nano-Catalysis Laboratory, KAUST Catalysis Centre, King Abdullah University of Science and Technology, Thuwal, KSA

Joaquín García-Álvarez, Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, Oviedo, Spain

Sergio E. García-Garrido, Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, Oviedo, Spain

Anirban Ghosh, Tata Chemicals Ltd, Innovation Center, Pune, India

Zhong He, Department of Chemical, Biological and Pharmaceutical Engineering, New Jersey Institute of Technology, Newark, NJ, USA

Balaji R. Jagirdar, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India

Suresh Babu Kalidindi, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India; Anorganische Chemie II, Ruhr Universität Bochum, Bochum, Germany

Kiyotomi Kaneda, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, Japan

Deepa Khushalani, Materials Chemistry Group, Tata Institute of Fundamental Research, Mumbai, India

Rajiv Kumar, Tata Chemicals Ltd, Innovation Center, Pune, India

Debasish Kundu, Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India

Brigid Lanigan, Department of Chemistry, Green Chemistry Centre of Excellence, University of York, Heslington, York, UK

Jin Hyung Lee, Korea Institute of Ceramic Engineering and Technology, Seoul, South Korea

Soo Youn Lee, Korea Institute of Ceramic Engineering and Technology, Seoul, South Korea

Yong Li, State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China

Jones Limberger, Laboratory of Molecular Catalysis, Institute of Chemistry, UFRGS, Porto Alegre, Brazil

Gaoqing Lu, ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering and AIBN, The University of Queensland, Qld, Australia

Biswajit Mishra, Materials Chemistry Group, Tata Institute of Fundamental Research, Mumbai, India

Takato Mitsudome, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, Japan

Adriano L. Monteiro, Laboratory of Molecular Catalysis, Institute of Chemistry, UFRGS, Porto Alegre, Brazil

Nirmalya Mukherjee, Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India

K. S. Nagabhushana, Tata Chemicals Ltd, Innovation Center, Pune, India

Carmen Nájera, Department of Organic Chemistry and Institute of Organic Synthesis, University of Alicante, Alicante, Spain

Radha Narayanan, Department of Chemistry, University of Rhode Island, Kingston, RI, USA

Brindaban C. Ranu, Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India

Debabrata Rautaray, Tata Chemicals Ltd, Innovation Center, Pune, India

Liane M. Rossi, Laboratory of Nanomaterials and Catalysis, Institute of Chemistry, USP, São Paulo, Brazil

Debasree Saha, Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India

Robert W. J. Scott, Department of Chemistry, University of Saskatchewan, Saskatoon, SK, Canada

K. K. Sharma, Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA

Wenjie Shen, State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China

Peter S. Shuttleworth, Departamento de Física de Polímeros, Elastómeros y Aplicaciones Energéticas, Instituto de Ciencia y Tecnología de Polímeros, CSIC, Madrid, Spain

R. Silva, Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA

Lianzhou Wang, ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering and AIBN, The University of Queensland, Qld, Australia

Xianqin Wang, Department of Chemical, Biological and Pharmaceutical Engineering, New Jersey Institute of Technology, Newark, NJ, USA

Zhi-Kang Xu, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China

Xu Zong, ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering and AIBN, The University of Queensland, Qld, Australia

1

INTRODUCTION TO NANOCATALYSIS

Vivek Polshettiwar and Tewodros Asefa

Catalysis provides sustainable and cost-effective methods to transform raw materials into valuable chemicals. Thus, catalytic processes have long become essential to solving the energy and environmental challenges that we currently face around the globe. Catalysis can be broadly divided into homogeneous and heterogeneous catalysis. Homogeneous catalysis involves catalysts and reactants in the same phase.1 As homogeneous catalysts are generally soluble molecular or ionic compounds, they have more easily accessible active catalytic sites, and thus often exhibit good catalytic activity. Moreover, their structures and functional groups can easily be changed to result in chemo-, regio-, and enantioselectivity. However, despite their many advantages and being widely used in industry, homogeneous catalysts do have some disadvantages, which is mainly to do with the fact that they are difficult to separate from the final products or reaction mixtures. Furthermore, even with the use of numerous techniques, such as chromatography, distillation, or extraction, the removal of trace amounts of residual catalytic species from the reaction mixture is always challenging in the case of homogeneous catalysis. This is an important issue that requires attention, given the fact that the presence of trace amounts of catalytic moieties, especially metallic ones, is strictly regulated in the commodity chemicals and pharmaceutical products, which are often produced using catalysts. All of these issues together, therefore, pose major hurdles for homogeneous catalysts, making many of them to have only limited applications.

Some of these drawbacks of homogeneous catalysts can be overcome by supporting the homogeneous catalytic species on solid support materials and producing their corresponding solid catalysts, known as heterogeneous catalysts.2 The general approach behind the synthesis of heterogeneous catalysts involves either the entrapment (immobilization) or the attachment of an active catalytic moiety on the solid support material. The former can be accomplished by letting the catalytic species to adsorb on the solid support materials, whereas the latter can be realized by tethering the catalytic groups on the support materials with covalent bonds, preferably with strong covalent bonds that can tolerate severe reaction conditions. Because of the physical attachment of the catalytic groups onto the solid support materials, heterogeneous catalysts often possess numerous advantages, such as their ease of handling, efficient recovery, enhanced stability and shelf-life, and reusability. However, because the reactants and the catalysts in heterogeneous catalysis must necessarily be in two different phases, the interaction between the reactant and the catalyst is reduced. This, in turn, can result in reduced overall catalytic activity in heterogeneous catalysts compared with their homogeneous counterparts. Possible leaching of active catalytic sites from the solid support materials, either from the cleavage of the covalent bonds between the catalytic groups and the solid support material or from the possible desorption of the catalytic groups off the solid support material, can also be an issue for some heterogeneous catalytic systems. Although the concentration of trace metals can often be much smaller in heterogeneous catalytic systems compared with that in the corresponding homogeneous catalytic systems, such possible leached trace metals in heterogeneous catalytic systems might still require separation from final products.

To overcome some of the limitations associated with both homogeneous and heterogeneous catalysts, new catalytic systems were needed that could have the advantages of both homogeneous and heterogeneous catalytic systems, allow all catalytic active sites to be accessible and effective (i.e., give good catalytic activity, selectivity, and yield), and make catalyst separation easily possible (i.e., stable catalyst, catalyst recovery, and catalyst reuse). Nanocatalysts and nanocatalysis could meet the need of such new catalyst systems (Figure 1.1).

Figure 1.1 Nanocatalysis can bridge the gap between homogeneous and heterogeneous catalysis, bring together the advantages of both homogeneous and heterogeneous catalysts, and overcome some of the issues associated with both homogeneous and heterogeneous catalytic systems.

WHAT IS NANOCATALYSIS?

The seemingly magical properties of nanoparticles have been unknowingly taken advantage of and used for various applications for centuries. Early uses of nanostructured materials include the third-century Lycurgus Cup,1 made of a dichroic glass of gold and silver nanoparticles, which made the cup look opaque green when lit from the outside and glowing red when lit from the inside. Similar shiny and sparkling ceramic glazes, which were used between the ninth and seventeenth centuries,2 also contained various metallic nanoparticles. The qualities of “Damascus” saber blades, used from 300 BCE to 1700 CE, including their excellent strength, toughness, and resistance to shattering, as well as their ability to remain extremely sharp, all came from their construction from carbon nanotubes and cementite nanowires.3 Even in the century-old Haber–Bosch process for ammonia synthesis,4 iron nanoparticles were present.5 It was also in the beginning of the twentieth century that Ostwald performed simple experimental demonstration that indicated the considerable increase of surface area from dividing cubes and its consequences for surface-dependent catalysis. In fact, we now use, perhaps still unknowingly too, huge varieties of nanomaterials in our daily lives6 as well as in industrial processes such as catalysis. As is often said, “nature makes and chemistry reshapes.”

Nanocatalysis has long become an important part of nanoscience.7 Nanoparticles can substitute conventional materials and serve as active and stable heterogeneous catalysts6 or as support materials for various catalytic groups.7 Due to their small sizes, catalytic-active nanoparticles have higher surface area and increased exposed active sites, and thereby improved contact areas with reactants, akin to those of homogeneous catalytic systems. At the same time, nanostructured catalysts can behave as heterogeneous catalysts; thus, they can also be easily separated from the reaction mixtures. In addition to their tunable catalytic activity and selectivity, often with activities close to homogeneous catalytic systems, the stability of nanocatalysts can be improved by tailoring the chemical and physical properties of the nanomaterials by various synthetic methods. For example, nanocatalysts with better activity, stability, and selectivity can be designed and synthesized merely by controlling the sizes, shapes, and morphologies of nanomaterials.7–9

NANOCATALYSIS: TRUTH OR HYPE?

There has been much discussion about the originality of the concept “nanocatalysis.” The question whether nanocatalysis is novel science or merely a fancy version of already known catalysis has often been posed. Several researchers have said, “Catalysis is always nano”. But, is this true? If it is true, then why is gold not active in its bulk state when it exhibits extraordinary catalytic activity when reduced to the nanoscale? Why does bulk cobalt oxide need high temperatures to oxidize CO to CO2, while cobalt oxide can catalyze the same reaction at very low temperatures at nanoscale size? There are a huge number of such examples (with their numbers increasing every day) of materials that show unprecedented catalytic activities when reduced from the bulk into nanoscale sizes.

Thus, the statement that “catalysis is always nano” may not be correct. What we can safely say, however, is that “catalytic interactions are always in the nanoscale.” More precisely, nanocatalysis (catalysis using nanomaterials), with catalytic interactions obviously in the nanoscale range, is at least a step beyond conventional catalysis (catalysis using bulk materials).

Nanocatalysts are extremely structure-sensitive, and their catalytic activity and selectivity depend heavily on the size, shape, and composition of the nanoparticles as well as their support materials. This can be exemplified by the largely unexpected results that gold nanoparticles smaller than 5 nm are very active catalysts even at subambient temperatures, while bulk and bigger size gold is inactive.8,0009 The benefit of the increased surface-to-volume ratio and the benefit of accessibility to specific sites (e.g., steps, edges, and corners) of nanoparticles to catalysis are now well-known.10,11 Therefore, multiple and extremely varied approaches to develop efficient nanocatalysts have been pursued. This includes the synthesis of metallic and metal oxide nanomaterials with different unique structures and shapes and their applications either as catalysts or as support materials for catalytic active species. Further research in this area or the development of nanocrystalline catalytic systems are also currently continuing. Furthermore, nanocatalytic reaction mechanisms are complex and not yet fully understood,12 making nanocatalysis a very exciting science with lots of room for further investigation.

Nanocatalysis can be considered as part of “green” science as well, because nanocatalysis often allows conducting chemical transformations in an environmentally friendly manner.13 This is possible, for example, by adopting magnetic nanocatalyst recovery,14 by mixing ionic liquids with metal nanoparticles,15 by creating electrodes with nanocatalysts with improved redox properties for energy-relevant applications, by encapsulating nanoparticles in nanoporous cavities of zeolites and molecular organic frameworks, and by controlling the shapes of metal and metal oxide nanoparticles to enhance their catalytic activities.16

The purpose of this book is to give readers a broad perspective and current information about catalytic protocols developed over the past several years involving nanomaterials as catalysts, (i.e., nanocatalysis). The 18 chapters in the book cover a huge range of fields, where a variety of nanomaterials are successfully used as catalysts. In each chapter, some discussion is made about the synthesis, characterization, and application of nanocatalysts in different chemical reactions. In addition, some typical detailed experimental procedures for the synthesis and characterization of nanocatalysts and how these nanocatalysts are employed to catalyze various important chemical reactions are presented.

The first six chapters are devoted to nanocatalysts or nanocatalysis for carbon–carbon (C—C) and carbon–heteroatom coupling reactions. While there are many C—C cross-coupling reactions, the Heck, Sonogashira, Suzuki–Miyaura, Kumada–Corriu, Negishi, Stille, Hiyama, and Fukuyama coupling reactions remain among the most broadly used in industrial applications. These C—C coupling reactions are essential in wide ranges of synthetic chemistry. This can be evidenced by the Nobel Prize in Chemistry awarded to Heck, Negishi, and Suzuki in 2010. In Chapter 2, Asefa and coworkers have reviewed the Heck reaction catalyzed by transition metal (mainly Pd) nanoparticles. The authors have also included other metal nanoparticles, such as Ru, Ni, and trimetallic Au–Ag–Pd, which have been recently shown to catalyze the Heck reaction.

The metal-catalyzed Suzuki cross-coupling reaction of aryl, vinyl, or alkyl halide or pseudohalides with organoboron reagents is among the most efficient synthetic methods to construct C—C bonds. The Suzuki reaction has, therefore, found widespread applications in organic syntheses. In Chapter 3, Rosi and coworkers have provided a critical review regarding the use of nanocatalysts for the Suzuki coupling reaction. Many advantages, such as catalyst recovery, catalyst reusability, and wide accessibility of the catalytic groups supported on organic, inorganic, or organic–inorganic hybrid solids and liquids (biphasic catalysis), are also discussed in detail.

Another important C—C coupling protocol is the Sonogashira reaction, which is often catalyzed by palladium-based catalysts and is capable of coupling a terminal sp-hybridized carbon in an alkyne with an sp2 carbon of an aryl or vinyl halide (or triflate). In Chapter 4, Chinchilla and Nájera have reviewed the development of nanocatalysts for this reaction. The authors have discussed the many different methods used to synthesize Pd nanocatalysts by immobilizing palladium nanoparticles on polymers, carbon nanostructures or inorganic materials for the Sonogashira reaction, and the applications of the materials as catalysts for the reaction. They have also included a review on the synthesis and use of non-palladium nanoparticles composed of copper, iron, ruthenium, or gold as catalysts for this reaction.

In Chapter 5, Banerjee and Scott have provided a review of the use of nanocatalysts for a variety of other types of C—C coupling reactions, namely the Hiyama reaction (involving organosilicon reactants), the Negishi reaction (involving organozinc reactants), the Stille reaction (involving organotin reactants), and the Kumada–Corriu reaction (involving organomagnesium reactants). The authors have discussed the synthesis and use of stabilized nanoparticles as catalysts for these coupling reactions. They have also discussed some newer synthetic strategies to nanocatalysts for these reactions from recent literature. Furthermore, they have presented mechanistic aspects of these coupling reactions as catalyzed by nanocatalysts, which include in situ conversions of precatalysts to actual zerovalent catalytic metal clusters.

In Chapter 6, Ranu and coworkers have reviewed the research works on nanocatalysts for carbon–heteroatom bond-forming reactions. The latter include carbon–sulfur, carbon–nitrogen, carbon–oxygen, and carbon–selenium reactions, which are used extensively in various chemical, material, and industrial processes. The authors have provided some accounts of the developments in the field of nanocatalysis and also discussed both the advantages and disadvantages of many nanocatalytic processes.

The next two chapters are devoted to nanocatalysis for fine chemical synthesis. In Chapter 7, Asefa and coworkers have reviewed nanocatalysis of three important and related reactions, namely the Henry, Aldol, and Knoevenagel reactions. The authors have also included several different synthetic approaches or methods developed to various nanocatalysts for these reactions.

The concept of atom economy, that is, designing synthetic methods to maximize the incorporation of all atoms used in a reaction into final reaction products, has emerged as a major goal for chemists in recent years. The skeletal rearrangements of organic molecules (e.g., isomerizations, cycloisomerizations, and pericyclic reactions) are typical notable examples of atom economical reactions because such reactions generate no by-products. In Chapter 8, García-Álvarez and coworkers have provided an up-to-date overview of published literature on the synthesis and applications of metal and metal oxide nanoparticles that can serve as catalysts for various rearrangement reactions of organic compounds.

The subsequent four chapters are devoted to the use of nanocatalysts for oxidation and hydrogenation reactions. Oxidation of alcohols is widely recognized as a fundamental and important transformation in both laboratory and industrial chemistry because the reaction results in carbonyl compounds that can serve as versatile solvents, polymer precursors, fragrances, and intermediates for fine chemicals and pharmaceuticals. In Chapter 9, Mitsudome and Kaneda have reviewed nanocatalysts based on inorganic material- or polymer-supported active metals of Ru, Pd, and Au for alcohol oxidation reaction in the liquid phase. The chapter not only provides good understanding of nanocatalysis for alcohol oxidation reactions but also highlights the issues related in this area that still need to be addressed in the future.

Besides their size, the shape of nanocatalysts plays an important role in determining the catalytic activity, selectivity, and stability of various nanocatalysts. In Chapter 10, Shen has summarized recent progress on morphologically controlled synthesis of Co3O4, Fe2O3, and CeO2 nanomaterials. Furthermore, the authors have described how tuning the shapes of these metal oxide nanocatalysts modulates their surface atomic configurations, and thereby catalytic properties for various reactions, including oxidation. In addition, the authors have discussed how morphology-dependent nanocatalysis has enabled our fundamental understanding of the structure–reactivity relationship in heterogeneous catalysis and provided some of their thoughts for some new direction for the development of highly efficient nanocatalysts.

Like oxidation, hydrogenation is an important reaction. In Chapter 11, Narayanan has reviewed the different types of nanocatalysts developed for hydrogenation reactions of alkenes, alkynes, and aromatic compounds. The author has also presented a survey of various nanocatalysts, including metal nanoparticles in colloidal solutions and metal nanoparticles adsorbed onto different supports, for hydrogenation and related reactions.

Along similar lines, Fihri and Polshettiwar have discussed nanocatalysts for hydrogenolysis reactions in Chapter 12. The authors have divided the chapter into two sections: the first one is on the nanocatalytic hydrogenolysis of glycerol, an important category of processes for glycerol conversion into commodity chemicals; and the second one is on the hydrogenolysis of alkanes, which potentially allows the conversion of natural gas into hydrocarbons with higher carbon numbers or liquid form. In both sections, various nanocatalytic systems that use mono- and bimetallic nanomaterials as well as metal nanoparticles modified by metal oxides are discussed.

The subsequent two chapters are devoted to the topic of nanomaterial-based photocatalysis. Photocatalysts increase the rate of a reaction when specifically activated by either ultraviolet (UV) or visible electromagnetic radiation. Using UV or visible light as a source of energy, especially sunlight, to promote photocatalytic reactions is of great importance to making catalytic protocols sustainable in terms of the environment and the economy. In Chapter 13, Mishra and Khushalani have summarized different types of nanomaterials used in photocatalysis, by paying particular attention to metal oxide-based photocatalytic materials and methods employed for their synthesis and their application as photocatalyst for the degradation of organic pollutants using visible light.

Water splitting is a reaction that can provide hydrogen from water; thus, it can serve as a potential energy source and solution to energy and environmental problems our world faces. Photocatalytic water splitting using nanomaterials as catalysts is extensively reviewed by Zong, Lu, and Wang in Chapter 14. The authors have started with a brief introduction of water-splitting reactions activated by nanocatalysts. They have also given an overview of semiconductor nanocatalysts by classifying them according to the type of light they can absorb or their absorption properties as well as elemental compositions. At the end of the chapter, they have discussed important criteria for the design and development of efficient and stable semiconductor nanocatalysts for water splitting and other related photochemical processes.

The next two chapters are devoted to the use of nanocatalysis to produce nonconventional sources of energy. Environmental concerns, process efficiency, and safety remain to be important issues in the development of catalysts, and these issues are stimulating the development and innovation of catalysts for sustainable H2 production. Hydrogen can actually be produced from renewable sources. In Chapter 15, He and Wang have reviewed the latest research advances related to H2 production from biomass and biomass-derived feedstock. They have also discussed the existing challenges behind conversion of both types of feedstock. They have included the use of synchrotron-based X-ray absorption spectroscopy as the characterization method for determination of the properties of nanocatalytic materials considered for renewable H2 production.

Along similar lines, in Chapter 16, Budarin, Shuttleworth, Lanigan, and Clark have provided a critical overview of biofuel production using nanocatalysts. The authors have discussed that nanocatalysis has been increasingly used or considered in biofuel production, for greener processing of various chemical raw materials, and for affording higher yields of desired products of various chemical processes. This, in turn, results in more economically favorable and cost-competitive processes compared with conventional chemical processes.

Owing to their large surface area, physical robustness, high resistance to organic solvents, and high thermal stability, nanomaterials are also attractive as support materials for immobilizing enzymes. Consequently, a variety of future applications are envisaged for nanomaterial-based biocatalysts in the medical, industrial, pharmaceutical, and environmental areas, including biosensor development, bioremediation, and food production. In Chapter 17, Lee and coworkers discussed nanomaterial-based biocatalysts and biocatalysis. The authors have also given an overview of the state-of-the-art technologies in practice and discussed this rapidly developing field that focuses on nanomaterial-based biocatalyst systems. Because nanomaterial-based biocatalysts have greater stability and higher shelf-lives, these materials enable traditional enzymes to find applications as catalysts in conventional chemical synthesis, where relatively harsh reaction conditions are often employed.

The last two chapters focus on the use of nanocatalysts in the chemical industry. In Chapter 18, Ghosh and coworkers have critically reviewed the role of nanocatalysis in the chemical industry. Using several case studies, they have explained how nanocatalysts have already been successfully used for several important chemical processes in industry.

In the final chapter, Chapter 19, Kalidindi and Jagirdar have discussed nanocatalysts in the context of activation of small molecules and their conversion to useful chemicals. The authors have discussed three nanocatalytic processes, namely CO oxidation on Au/metal oxide catalysts, direct synthesis of H2O2 from H2 and O2, and methanol synthesis from CO and CO2. These three reactions have great industrial and environmental importance.

In its entirety, this book provides fundamental understanding of nanocatalysis and a wealth of information on synthesis, characterization and applications of nanocatalysts. The book also provides an important and critical overview on how nanocatalysis can serve as a platform from which a virtually unlimited number of crucial chemical process issues can be resolved. The obvious applications of nanocatalysts will be in fine chemical synthesis, where refined nanocatalysts allow the production of desired products in higher yields. Another notable example where nanocatalysts have potential application is in energy (hydrogen) production from water, or a renewable source of energy with sunlight. Nanocatalysis can also a play significant role in resolving the energy and environmental challenges that we as a global society now face. Thus, nanocatalysis can help us take gigantic steps forward for the betterment of humankind through the use of tiny nanoscale particles.17

REFERENCES

1. Tait H., editor. Five Thousand Years of Glass. London: The British Museum Press; 1991.

2. Carboni S. Glass from Islamic Lands. London: Thames & Hudson, Ltd; 2001, p 51.

3. Reibold M., Paufler P., Levin A. A., Kochmann W., Pätzke N., Meyer D. C. Materials: Carbon nanotubes in an ancient damascus sabre. Nature 2006;444:286–286.

4. Smil V. Detonator of the population explosion. Nature 1999;400:415–416.

5. Rodriguez M. M., Bill W., Brennessel W. W., Holland P. L. N-2 reduction and hydrogenation to ammonia by a molecular iron-potassium complex. Science 2011;334:780–783.

6. Ozin G. A., Arsenault A. C., Cademartiri L., editors. Nanochemistry: A Chemical Approach to Nanomaterials, 2nd ed. Royal Society of Chemistry; 2008.

7. Astruc D., editor. Nanoparticles and Catalysis, Weinheim: Wiley-VCH Verlag GmbH; 2008.

8. Ishida T., Haruta M. Gold catalysts: Towards sustainable chemistry. Angew. Chem. Int. Ed. 2007;46:7154–7156.

9. Hashmi A. S. K., Hutchings G. J. Gold catalysis. Angew. Chem. Int. Ed. 2006;47:7896–7936.

10. Somorjai G. A., Frei H., Park J. Y. Advancing the frontiers in nanocatalysis, biointerfaces, and renewable energy conversion by innovations of surface techniques. J. Am. Chem. Soc. 2009;131:16589–16605.

11. Burda C., Chen X., Narayanan R., El-Sayed M. A. Chemistry and properties of nanocrystals of different shapes. Chem. Rev. 2005;105:1025–1102.

12. de Smit E., Swart I., Creemer J. F., Karunakaran C., Bertwistle D., Zandbergen H. W., de Groot F. M. F., Weckhuysen B. M. Nanoscale chemical imaging of a working catalyst by scanning transmission X-ray microscopy. Angew. Chem. Int. Ed. 2009;48:3632–3636.

13. Polshettiwar V., Varma R. S. Green chemistry by nan-catalysis. Green Chem. 2010;12:743–754.

14. Polshettiwar V., Luque R., Fihri A., Zhu H., Bouhrara M., Basset J. M. Magnetically recoverable nano-catalysts. Chem. Rev. 2011;111:3036–3075.

15. Fihri A., Bouhrara M., Nekoueishahraki B., Basset J. M., Polshettiwar V. Nano-catalysis for Suzuki coupling reaction. Invited for nobel issue. Chem. Soc. Rev. 2011;40:5181–5203.

16. Xie X., Li Y., Liu Z.-Q., Haruta M., Shen W. Low temperature oxidation of CO by Co3O4, Nanorods. Nature 2008;458:746–749.

17. Rothenberg G., editor. Catalysis—Concepts and Green Applications. Weinheim: Wiley-VCH Verlag GmbH; 2008.