Nanomaterials E-Book

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

Seitenzahl: 2686

Veröffentlichungsjahr: 2013

Beschreibung

Connecting inorganic chemistry to the hottest topic in materials science, this timely resource collects the contributions made by leading inorganic chemists towards nanomaterials research. The second volume in the “Wiley Encyclopedia of Inorganic Chemistry Methods and Applications Series,” this signature title concentrates on recent developments in the field and includes all key topics such as nanowires, nanotubes, biomineralization, supramolecular materials and much more.

This volume is also available as part of Encyclopedia of Inorganic Chemistry, 5 Volume Set.

This set combines all volumes published as EIC Books from 2007 to 2010, representing areas of key developments in the field of inorganic chemistry published in the Encyclopedia of Inorganic Chemistry. Find out more.

Leseprobe

EIC Books

Applications of Physical Methods to Inorganic and Bioinorganic ChemistryEdited by Robert A. Scott and Charles M. LukehartISBN 978-0-470-03217-6

Nanomaterials: Inorganic and Bioinorganic PerspectivesEdited by Charles M. Lukehart and Robert A. ScottISBN 978-0-470-51644-7

Forthcoming

Computational Inorganic and Bioinorganic ChemistryEdited by Edward I. Solomon, R. Bruce King and Robert A. ScottISBN 978-0-470-69997-3

Handbook of Radionuclides in the EnvironmentEdited by David AtwoodISBN 978-0-470-71434-8

Encyclopedia of Inorganic Chemistry

In 1994 John Wiley & Sons published the Encyclopedia of Inorganic Chemistry (EIC). This 8-volume work was well received by the community, and has become a standard publication in all libraries serving the inorganic, coordination chemistry, organometallic and bioinorganic communities. The 10-volume Second Edition of the Encyclopedia was published in print in 2005, and online in 2006, on the major reference platform Wiley InterScience:

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Encyclopedia of Inorganic Chemistry

Editorial Board

Editor-in-Chief

Robert H. CrabtreeYale University, New Haven, CT, USA

Section Editors

David A. AtwoodUniversity of Kentucky, Lexington, KY, USA

R. Bruce KingUniversity of Georgia, Athens, GA, USA

Charles M. LukehartVanderbilt University, Nashville, TN, USA

Robert A. ScottUniversity of Georgia, Athens, GA, USA

International Advisory Board

Michael BruceAdelaide, Australia

Fausto CalderazzoPisa, Italy

Tristram ChiversCalgary, Canada

Odile EisensteinMontpellier, France

C. David GarnerNottingham, UK

Malcolm GreenOxford, UK

Wolfgang HerrmannMunich, Germany

Jean-Marie LehnStrasbourg, France

François MatheyUniversity of California Riverside,CA, USA

Akira NakamuraOsaka, Japan

Jan ReedijkLeiden, The Netherlands

Vivian YamHong Kong

Contents

Cover

Title

Copyright

List of Contributors

Series Preface

Volume Preface

Biologically Templated Nanostructure Assemblies

1 INTRODUCTION

2 CHEMICAL PROCEDURES FOR BIOTEMPLATED NANOSTRUCTURES

3 BIOTEMPLATING

4 CONCLUSIONS AND SUMMARY

5 RELATED ARTICLES

6 ABBREVIATIONS AND ACRONYMS

7 REFERENCES

Biomedical Applications of Magnetic Nanoparticles

1 INTRODUCTION

2 MAGNETIC NANOPARTICLES AND AQUEOUS MAGNETIC FLUIDS

3 IN VITRO DIAGNOSTIC APPLICATIONS

4 IN VIVO APPLICATIONS

5 OUTLOOK AND FUTURE CHALLENGES

6 ACKNOWLEDGMENTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Biomimetic Chemistry of Hybrid Materials

1 INTRODUCTION

2 SWITCHING OF MORPHOLOGY

3 GATED NANOCHEMISTRY

4 BIOMIMETIC BINDING POCKETS

5 BIOMIMETIC MOTORS

6 CONCLUSIONS

7 ACKNOWLEDGMENTS

8 END NOTES

9 RELATED ARTICLES

10 ABBREVIATIONS AND ACRONYMS

11 REFERENCES

Biomineralization: Peptide-Mediated Synthesis of Materials

1 INTRODUCTION

2 UNCONSTRAINED PEPTIDE TEMPLATES

3 MATERIALS-IMMOBILIZED PEPTIDE TEMPLATES

4 BIOLOGICAL PEPTIDE SCAFFOLDS

5 FUTURE DIRECTIONS

6 ABBREVIATIONS AND ACRONYMS

7 REFERENCES

Biomineralization: Self-Assembly Processes

1 INTRODUCTION

2 CRYSTALLIZATION PATHWAYS VIA SELF-ASSEMBLY PROCESSES

3 BIOMINERALIZATION IN NATURE

4 BIOMINERALIZATION VIA ORGANIC MOLECULE DIRECTING SELF-ASSEMBLY

5 CONCLUSION AND PERSPECTIVES

6 ACKNOWLEDGMENTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Carbon Nanotubes, Multi-Walled

1 CARBON NANOTUBE SYNTHESIS

2 CHEMICAL REACTIVITY OF MWNTs

3 CARBON NANOTUBE POLYMER COMPOSITES

4 CONCLUSIONS

5 RELATED ARTICLES

6 ABBREVIATIONS AND ACRONYMS

7 REFERENCES

Carbon Nanotubes, Single-Walled: Functionalization by Intercalation

1 INTRODUCTION

2 THE SINGLE-WALLED CARBON NANOTUBES HOST SYSTEM

3 INTERCALATION INTO SINGLE-WALLED CARBON NANOTUBE BUNDLES

4 INTERCALATION INTO THE TUBES

5 NANOCHEMISTRY USING SINGLE-WALLED CARBON NANOTUBES AS A REACTION FURNACE

6 ACKNOWLEDGMENTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Carbon Nanotubes: Fluorinated Derivatives

1 INTRODUCTION

2 FLUORINATION OF CARBON NANOTUBES

3 STRUCTURE OF FLUORONANOTUBES

4 SOLVATION PROPERTIES OF FLUORONANOTUBES

5 CHEMICAL PROPERTIES OF FLUORONANOTUBES

6 SUMMARY

7 ACKNOWLEDGMENTS

8 ABBREVIATIONS AND ACRONYMS

9 REFERENCES

Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

1 INTRODUCTION

2 POLYMERIC/CARBON NANOTUBES COMPOSITES

3 ELECTRICAL PROPERTIES AND APPLICATIONS

4 THERMAL CONDUCTIVE NANOCOMPOSITES

5 SUMMARY

6 ACKNOWLEDGMENTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Endohedral Fullerenes

1 INTRODUCTION

2 THE ENDOHEDRAL FULLERENES—A GENERAL VIEW

3 NOVEL ENDOHEDRAL FULLERENES

4 ENDOHEDRAL FULLERENES—NEW STRUCTURES AND PERSPECTIVES

5 PROPERTIES OF ENDOHEDRAL FULLERENES

6 APPLICATIONS OF ENDOHEDRAL FULLERENES

7 SUMMARY

8 ACKNOWLEDGMENTS

9 RELATED ARTICLES

10 ABBREVIATIONS AND ACRONYMS

11 REFERENCES

Fullerenes: Metal Complexes

1 INTRODUCTION

2 MONONUCLEAR METAL COORDINATION TO FULLERENES

3 COORDINATION OF METAL CLUSTERS TO FULLERENES

4 REDOX-ACTIVE FILMS PREPARED BY REDUCTION OF SOLUTIONS OF FULLERENES AND TRANSITION METAL COMPLEXES

HETEROFULLERENES—METAL ATOMS AS PART OF THE FULLERENE CAGE

6 COCRYSTALLIZATION OF FULLERENES WITH METAL COMPLEXES

7 CONCLUSION

8 RELATED ARTICLES

9 ABBREVIATIONS AND ACRONYMS

10 REFERENCES

Fullerenes: Nanoscale-Ordered Materials

1 INTRODUCTION

2 CONCLUDING REMARKS

3 ACKNOWLEDGMENTS

4 ABBREVIATIONS AND ACRONYMS

5 REFERENCES

Gold Nanoparticles as Chemical Catalysts

1 INTRODUCTION

2 GENERAL CONSIDERATIONS

3 LOADING GOLD NANOPARTICLES ON SiO2 SUPPORTS

4 PREMODIFICATION OF SUPPORTS BY METAL OXIDES

5 POSTMODIFICATION OF SUPPORTED GOLD CATALYSTS

6 GOLD ON NANOSTRUCTURED AND NANOSIZED SUPPORTS

7 SYNTHESIS OF SUPPORTED GOLD CATALYSTS USING OTHER METHODS

8 CONCLUDING REMARKS

9 ACKNOWLEDGMENTS

10 ABBREVIATIONS AND ACRONYMS

11 REFERENCES

Gold Nanoparticles: Monolayer-Protected Scaffolds and Building Blocks

1 INTRODUCTION

2 GOLD NANOPARTICLES: SYNTHESIS AND CHARACTERIZATION

3 CONTROLLED ASSEMBLY OF NANOPARTICLES

4 BIOLOGICAL INTERACTION OF NANOPARTICLE: ASSEMBLY AND APPLICATIONS

5 CONCLUSIONS AND FUTURE DIRECTIONS

6 ABBREVIATIONS AND ACRONYMS

7 REFERENCES

Inorganic Nanobelt Materials

1 INTRODUCTION

2 SYNTHETIC STRATEGIES AND PRINCIPLES

3 ELEMENTAL NANOBELTS

4 OXIDE NANOBELTS

5 HYDROXYL SULFATE NANOBELTS

6 METAL CHALCOGENIDE NANOBELTS

7 METAL ARSENIDE AND PHOSPHIDE NANOBELTS

8 NITRIDE NANOBELTS

9 CARBON AND METAL CARBIDE NANOBELTS

10 PROPERTIES AND APPLICATIONS

11 CONCLUSIONS AND OUTLOOK

12 ACKNOWLEDGMENTS

13 ABBREVIATIONS AND ACRONYMS

14 REFERENCES

Inorganic Nanocrystals: Patterning and Assembling

1 INTRODUCTION

2 ASSEMBLING AND PATTERNING OF INORGANIC NANOCRYSTALS

3 PRECISION FABRICATION OF ASSEMBLING COMPONENTS

4 FUNCTIONALIZED COLLOIDAL NCs FOR ASSEMBLING AND PATTERNING

5 NC-BASED NANOCOMPOSITES FOR ASSEMBLING AND PATTERNING

6 LITHOGRAPHY-RELATED METHODS AND OTHER NONCONVENTIONAL PATTERN TECHNIQUES

7 BIOMIMETIC AND BIODIRECTED ASSEMBLING OF INORGANIC NCs

8 CONCLUSIONS AND PERSPECTIVES

9 ACKNOWLEDGMENT

10 ABBREVIATIONS AND ACRONYMS

11 FURTHER READING

12 REFERENCES

Inorganic Nanomaterials Synthesis Using Alkalide Reduction

1 INTRODUCTION: FROM METAL AMMONIA SOLUTIONS TO ALKALIDES AND ELECTRIDES

2 ALKALIDE REDUCTION

3 PREPARATION OF ALKALIDE, ELECTRIDES, AND THEIR SOLUTIONS

4 NANOPARTICLE SIZE, DISTRIBUTION, AND SHAPE

5 SINGLE-ELEMENT NANOMATERIALS

6 BINARY NANOMATERIALS: ALLOYS AND INTERMETALLIC COMPOUNDS

7 BINARY NANOMATERIALS: COMPOUNDS

8 TERNARY NANOMATERIALS

9 SUPPORTED NANOMATERIALS

10 CONCLUSIONS

11 ACKNOWLEDGMENTS

12 RELATED ARTICLES

13 ABBREVIATIONS AND ACRONYMS

14 REFERENCES

Inorganic Nanomaterials Synthesis Using Ionic Liquids

1 INTRODUCTION

2 STRUCTURE OF IONIC LIQUIDS AND IMPACT FOR NANOMATERIALS SYNTHESIS

3 INORGANIC NANOMATERIALS SYNTHESIS USING IONIC LIQUIDS

4 CONCLUSION

5 ACKNOWLEDGMENTS

6 RELATED ARTICLES

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Inorganic Nanomaterials Synthesis Using Liquid Crystals

1 INTRODUCTION

2 BASES OF NANOCASTING

3 MESOSTRUCTURED THIN FILMS OBTAINED BY EISA

4 THE EISA METHOD

5 INFLUENCE OF THERMAL TREATMENT ON THE FILM STRUCTURE

6 COMPLEX ARCHITECTURES FOR MESOPOROUS THIN FILMS

7 SYNTHESES IN LIQUID CRYSTALS

8 PROPERTIES AND APPLICATIONS

9 CONCLUSION: VERSATILITY OF SOFT MATTER

10 ABBREVIATIONS AND ACRONYMS

11 REFERENCES

Inorganic Nanotubes

1 INTRODUCTION

2 GEOMETRY AS CRITERION FOR STABILITY

3 SYNTHESIS OF INORGANIC NANOTUBES

4 MORPHOLOGY OF INORGANIC NANOTUBES

5 APPLICATIONS OF INORGANIC NANOTUBES

6 CONCLUDING REMARKS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Inorganic Semiconductor Nanomaterials for High-Performance Flexible Electronics

1 INTRODUCTION

2 SYNTHESIS OF INORGANIC SEMICONDUCTOR NANOWIRES, NANORIBBONS AND NANOMEMBRANES

3 ASSEMBLY OF INORGANIC SEMICONDUCTOR NANOMATERIALS

4 APPLICATIONS IN FLEXIBLE AND STRETCHABLE ELECTRONICS

5 CONCLUDING REMARKS

6 ABBREVIATIONS AND ACRONYMS

7 REFERENCES

Liquid-Phase Synthesis of Inorganic Nanoparticles

1 INTRODUCTION

2 MECHANISM OF PRECIPITATION OF NANOPARTICLES IN LIQUID MEDIA

3 LIQUID-PHASE SYNTHESIS OF NOBLE METAL NANOPARTICLES

4 LIQUID-PHASE SYNTHESIS OF TRANSITION METAL NANOPARTICLES AND ALLOYS

5 SUMMARY AND OUTLOOK

6 RELATED ARTICLES

7 ABBREVIATIONS AND ACRONYMS

8 FURTHER READING

9 REFERENCES

Metal Oxide Nanoparticles

1 INTRODUCTION: THE WORLD OF OXIDE NANOMATERIALS

2 SYNTHESIS OF NANOPARTICULATED OXIDES

3 PROPERTIES OF NANOPARTICULATED OXIDES

4 CASE STUDIES

5 ACKNOWLEDGMENTS

6 ABBREVIATIONS AND ACRONYMS

7 REFERENCES

Monodisperse Magnetic Nanoparticles: Chemical Synthesis and Surface Modification

1 INTRODUCTION

2 MAGNETIC FERRITE MFe2O4 NANOPARTICLES

3 METALLIC Fe AND Co NANOPARTICLES

4 MAGNETIC ALLOY NANOPARTICLES: THE CASE OF FePt AND CoFe

5 MULTICOMPONENT MAGNETIC NANOPARTICLES

6 SURFACE MODIFICATION OF MAGNETIC NANOPARTICLES AND THEIR APPLICATIONS

7 CONCLUSIONS

8 ACKNOWLEDGMENTS

9 RELATED ARTICLES

10 ABBREVIATIONS AND ACRONYMS

11 REFERENCES

Molecular and Supramolecular Arrays of the [Re6(μ3-Se)8]2+ Core-Containing Clusters

1 INTRODUCTION

2 LIGAND-BRIDGED ARRAYS OF THE [Re6(μ3-Q)8]2+ CORE-CONTAINING CLUSTERS

3 SUPRAMOLECULAR CLUSTER ARRAYS

4 SUMMARY AND OUTLOOK

5 ACKNOWLEDGMENTS

6 RELATED ARTICLES

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Multicolor Quantum Dots in Molecular Profiling of Cancer Cells and Tissues

1 INTRODUCTION

2 OPTICAL PROPERTIES OF QUANTUM DOTS

3 QD SYNTHESIS, COATING, AND BIOCONJUGATION

4 MULTIPLEXED CELLULAR AND TISSUE IMAGING WITH QUANTUM DOTS

5 CONCLUSIONS

6 ACKNOWLEDGMENTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Nano/Microporous Materials: Crystalline Metal-Chalcogenide Superlattices

1 INTRODUCTION

2 TETRAHEDRAL CHALCOGENIDE CLUSTERS AS BUILDING BLOCKS

3 METAL CHALCOGENIDES CONSTRUCTED FROM SUPERTETRAHEDRAL CLUSTERS

4 METAL CHALCOGENIDES CONSTRUCTED FROM PENTASUPERTETRAHEDRAL CLUSTERS

5 METAL CHALCOGENIDES CONSTRUCTED FROM CAPPED SUPERTETRAHEDRAL CLUSTERS

6 METAL CHALCOGENIDES CONSTRUCTED FROM DIFFERENT TETRAHEDRAL CLUSTERS

7 SELECTED PROPERTIES OF OPEN-FRAMEWORK CHALCOGENIDES

8 POTENTIAL APPLICATIONS

9 ACKNOWLEDGMENTS

10 RELATED ARTICLES

11 ABBREVIATIONS AND ACRONYMS

12 REFERENCES

Nano/Microporous Materials: Hydrogen-Storage Materials

1 INTRODUCTION

2 GENERAL CONSIDERATIONS

3 CARBON MATERIALS

4 INORGANIC MATERIALS

5 HYBRID ORGANIC-INORGANIC MATERIALS

6 CONCLUSIONS

7 RELATED ARTICLES

8 ABBREVIATIONS AND ACRONYMS

9 REFERENCES

Nano/Microporous Materials: Hydrothermal Synthesis of Zeolites

1 INTRODUCTION

2 PRESENTATION OF A ZEOLITE SYNTHESIS SYSTEM

3 INITIAL COMPOSITION AND CHEMICAL REACTIONS

4 ZEOLITE CRYSTALLOGENESIS

5 ZEOLITE CRYSTAL ENGINEERING

6 CONCLUDING REMARKS

7 ACKNOWLEDGMENTS

8 ABBREVIATIONS AND ACRONYMS

9 REFERENCES

Nano/Microporous Materials: Mesoporous and Surface-Functionalized Mesoporous Carbon

1 INTRODUCTION

2 SYNTHESIS OF MESOPOROUS CARBONS THROUGH THE HARD TEMPLATE METHOD

3 SYNTHESIS OF MESOPOROUS CARBONS THROUGH THE SOFT TEMPLATE METHOD

4 FUNCTIONALIZATION OF MESOPOROUS CARBON MATERIALS

5 CONCLUDING REMARKS

6 ACKNOWLEDGMENTS

7 RELATED ARTICLES

8 ABBREVIATIONS AND ACRONYMS

9 REFERENCES

Nano/Microporous Materials: Metal-Ion Sorption Materials

1 INTRODUCTION

2 MICROPOROUS AND MESOPOROUS MATERIALS

3 NANOMATERIALS

4 CONCLUSIONS

5 ABBREVIATIONS AND ACRONYMS

6 REFERENCES

Nano/Microporous Materials: Nanostructured Layered Double Hydroxides

1 INTRODUCTION

2 NANOSIZED LDH PARTICLES PREPARATION

3 NANOSIZED PARTICLES SYNTHESIS FROM LDH STRUCTURE

4 CONCLUDING REMARKS

5 ABBREVIATIONS AND ACRONYMS

6 REFERENCES

Nano/Microporous Materials: Transition Metal Cyanides

1 INTRODUCTION

2 CYANO-BRIDGED POLYGONS

3 METAL-CYANIDE CAGES

4 ACKNOWLEDGMENT

5 RELATED ARTICLES

6 ABBREVIATIONS AND ACRONYMS

7 REFERENCES

Nanocomposite Materials: Polyhedral Silsesquioxanes

1 INTRODUCTION

2 NANOCOMPOSITES

3 POLYHEDRAL OLIGOMERIC SILSESQUIOXANES

4 POSS POLYMERS–COPOLYMERS

5 BIOMEDICAL APPLICATION OF POSS-CONTAINING NANOCOMPOSITES

6 FUTURE PROSPECTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Nanocomposite Materials: Semiconductors in Zeolites

1 INTRODUCTION

2 SILICON

3 PNICTIDES

4 OXIDES

5 CHALCOGENS AND CHALCOGENIDES

6 NOBLE METAL HALIDES

7 PERSPECTIVES

8 ABBREVIATIONS AND ACRONYMS

9 REFERENCES

Nanoporous Metal Phosphonates

1 INTRODUCTION

2 CRYSTALLINE MICROPOROUS FRAMEWORK METAL PHOSPHONATES

3 LAYERED BISPHOSPHONATES AS POROUS MATERIALS

4 MESOPOROUS METAL PHOSPHONATES PREPARED VIA SURFACTANT MICELLE-TEMPLATING ROUTES

5 SUMMARY

6 ACKNOWLEDGMENTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Nanostructured Catalysts: Controlling Single-Site Composition

1 INTRODUCTION

2 NANOSTRUCTURED AND SINGLE-SITE CATALYSTS: STRUCTURAL AND CHEMICAL DEFINITIONS

3 ZEOLITES: PROTOTYPICAL NANOSTRUCTURED CATALYSTS

4 METAL-ORGANIC-FRAMEWORK MATERIALS

5 SINGLE-SITE CATALYSTS ON NONZEOLITIC NANOSTRUCTURED METAL OXIDE SUPPORTS

6 IMPRINTED HETEROGENEOUS CATALYSTS

7 SUMMARY AND FUTURE OUTLOOK

8 ABBREVIATIONS AND ACRONYMS

9 REFERENCES

Periodic Mesoporous Organosilicas

1 INTRODUCTION

2 SYNTHESIS AND ASSEMBLY OF PMOs

3 PMO STRUCTURES

4 MORPHOLOGIES OF PMOs

5 SUMMARY AND OUTLOOK

6 ACKNOWLEDGMENTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Semiconductor Nanocrystals: Doped Compositions

1 INTRODUCTION

2 SYNTHESIS OF DOPED COLLOIDAL SEMICONDUCTOR NANOCRYSTALS: THEORY AND PRACTICE

3 CHARACTERIZATION OF DOPED SEMICONDUCTOR NANOCRYSTALS

4 TRANSITION METAL DOPING

5 LANTHANIDE DOPING

6 ELECTRONIC DOPING

7 NEW DEVELOPMENTS

8 SUMMARY

9 ACKNOWLEDGMENTS

10 END NOTES

11 RELATED ARTICLES

12 ABBREVIATIONS AND ACRONYMS

13 REFERENCES

Semiconductor Nanowires

1 INTRODUCTION

2 NANOWIRE SYNTHESIS

3 NANOWIRE STRUCTURE

4 NANOWIRE PROCESSING AND MANIPULATION: TOWARD APPLICATIONS

5 CONCLUDING REMARKS

6 ACKNOWLEDGMENTS

7 RELATED ARTICLES

8 ABBREVIATIONS AND ACRONYMS

9 FURTHER READING

10 REFERENCES

Semiconductor/Ceramic Nanocomposites: Synthesis, Characterization, and Properties

1 INTRODUCTION AND SCOPE

2 ELEMENTAL SEMICONDUCTORS

3 II–VI/CERAMIC NANOCOMPOSITES

5 III–V/CERAMIC NANOCOMPOSITES

6 CONCLUSION

7 RELATED ARTICLES

8 ABBREVIATIONS AND ACRONYMS

9 REFERENCES

Supramolecular Materials: Assemblies Based on Square-Complexation

1 INTRODUCTION

2 DISCRETE STRUCTURES

3 SQUARE COMPLEXATION IN EXTENDED STRUCTURES

4 CONCLUSIONS

5 RELATED ARTICLES

6 ABBREVIATIONS AND ACRONYMS

7 REFERENCES

Supramolecular Materials: Metal–Quinonoid Complexes

1 INTRODUCTION

2 SELF–ASSEMBLY

3 CATALYSIS

4 METALLIC NANOPARTICLE (NP) FUNCTIONALIZATION

5 CONCLUSIONS

6 ACKNOWLEDGMENTS

7 ABBREVIATIONS AND ACRONYMS

8 REFERENCES

Functional Supramolecular Hybrid Materials

1 INTRODUCTION

2 ENHANCED FUNCTION FROM PREORGANIZATION ON SURFACES

3 CONTROLLED ASSEMBLY, DISASSEMBLY, AND SWITCHING

4 CONCLUSIONS

5 ACKNOWLEDGMENTS

6 END NOTES

7 RELATED ARTICLES

8 ABBREVIATIONS AND ACRONYMS

9 REFERENCES

Index

Contributors

Jong-Hyun Ahn

University of Illinois at Urbana-Champaign, Urbana, IL, USA and Sungkyunkwan University, Suwon, Korea

•  Inorganic Semiconductor Nanomaterials for High-Performance Flexible Electronics

Rodney Andrews

University of Kentucky, Lexington, KY, USA

•  Carbon Nanotubes, Multi-Walled

Alfred J. Baca

University of Illinois at Urbana-Champaign, Urbana, IL, USA

•  Inorganic Semiconductor Nanomaterials for High-Performance Flexible Electronics

Dhirendra Bahadur

IIT Bombay, Mumbai, India

•  Biomedical Applications of Magnetic Nanoparticles

Raheleh Bakhshi

University College London, London, UK

•  Nanocomposite Materials: Polyhedral Silsesquioxanes

Alan L. Balch

University of California—Davis, Davis, CA, USA

•  Fullerenes: Metal Complexes

Craig E. Barnes

University of Tennessee, Knoxville, TN, USA

•  Nanostructured Catalysts: Controlling Single-Site Composition

Silke S. Behrens

Institute of Technical Chemistry, Karlsruhe, Germany

•  Biologically Templated Nanostructure Assemblies

Cédric Boissière

LCMC, CNRS—University of Paris 6, Paris, France

•  Inorganic Nanomaterials Synthesis Using Liquid Crystals

Xianhui Bu

California State University, Long Beach, CA, USA

•  Nano/Microporous Materials: Crystalline Metal-Chalcogenide Superlattices

Li Cao

Clemson University, Clemson, SC, USA

•  Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

Daniela Caruntu

University ofNew Orleans, New Orleans, LA, USA

•  Liquid-Phase Synthesis of Inorganic Nanoparticles

Gabriel Caruntu

University of New Orleans, New Orleans, LA, USA

•  Liquid-Phase Synthesis of Inorganic Nanoparticles

Kelby Cassity

University ofKentucky, Lexington, KY, USA

•  Carbon Nanotubes, Multi-Walled

Christopher J. Chancellor

University of California—Davis, Davis, CA, USA

•  Fullerenes: Metal Complexes

Shaofeng Chen

University of Science and Technology of China, Hefei, People’s Republic of China

•  Biomineralization: Self-Assembly Processes

David J. Collins

Miami University, Oxford, OH, USA

•  Nano/Microporous Materials: Hydrogen-Storage Materials

•  Nano/Microporous Materials: Transition Metal Cyanides

Roberto Comparelli

Italian National Research Council—CNR, Istituto per i Processi Chimici e fisici, Bari, Italy

•  Inorganic Nanocrystals: Patterning and Assembling

Maria Lucia Curri

Italian National Research Council—CNR, Istituto per i Processi Chimici e fisici, Bari, Italy

•  Inorganic Nanocrystals: Patterning and Assembling

Sheng Dai

Oak Ridge National Laboratory, Oak Ridge, TN, USA

•  Gold Nanoparticles as Chemical Catalysts

•  Nano/Microporous Materials: Mesoporous and Surface-Functionalized Mesoporous Carbon

Nicoletta Depalo

Italian National Research Council—CNR, Istituto per i Processi Chimici e fisici, Bari, Italy and Università degli Studi di Bari, Bari, Italy

•  Inorganic Nanocrystals: Patterning and Assembling

Etienne Duguet

Université de Bordeaux, Bordeaux, France

•  Biomedical Applications of Magnetic Nanoparticles

Lothar Dunsch

Leibniz-Institute for Solid State and Materials Research (IFW) Dresden, Dresden, Germany

•  Endohedral Fullerenes

Elisabetta Fanizza

Italian National Research Council—CNR, Istituto per i Processi Chimici e fisici, Bari, Italy and Università degli Studi di Bari, Bari, Italy

•  Inorganic Nanocrystals: Patterning and Assembling

Pingyun Feng

University of California-Riverside, Riverside, CA, USA

•  Nano/Microporous Materials: Crystalline Metal-Chalcogenide Superlattices

Marcos Fernández-García

Instituto de Catalisis y Petroleoquímica, CSIC, Madrid, Spain

•  Metal Oxide Nanoparticles

Xiaohu Gao

University of Washington, Seattle, WA, USA

•  Multicolor Quantum Dots in Molecular Profiling of Cancer Cells and Tissues

Hossein Ghanbari

University College London, London, UK

•  Nanocomposite Materials: Polyhedral Silsesquioxanes

Andreas Goldbach

Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China

•  Nanocomposite Materials: Semiconductors in Zeolites

David Grosso

LCMC, CNRS—University of Paris 6, Paris, France

•  Inorganic Nanomaterials Synthesis Using Liquid Crystals

Lingrong Gu

Clemson University, Clemson, SC, USA

•  Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

Dirk M. Guldi

Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany

•  Fullerenes: Nanoscale-Ordered Materials

David T. Hobbs

Savannah River National Laboratory, Aiken, SC, USA

•  Nano/Microporous Materials: Metal-Ion Sorption Materials

Jennifer A. Hollingsworth

Los Alamos National Laboratory, Los Alamos, NM, USA

•  Semiconductor Nanocrystals: Doped Compositions

Stuart L. James

Queen’s University Belfast, Belfast, UK

•  Supramolecular Materials: Assemblies Based on Square-Complexation

Ruben Y. Kannan

University College London, London, UK and Royal Free Hampstead NHS Trust Hospital, London, UK

•  Nanocomposite Materials: Polyhedral Silsesquioxanes

Valery N. Khabashesku

Rice University, Houston, TX, USA

•  Carbon Nanotubes: Fluorinated Derivatives

Sang Bok Kim

Brown University, Providence, RI, USA

•  Supramolecular Materials: Metal-Quinonoid Complexes

Brian A. Korgel

University of Texas at Austin, Austin, TX, USA

•  Semiconductor Nanowires

Hans Kuzmany

Universität Wien, Vienna, Austria

•  Carbon Nanotubes, Single-Walled: Functionalization by Intercalation

Oleksandr V. Kuznetsov

Rice University, Houston, TX, USA

•  Carbon Nanotubes: Fluorinated Derivatives

Fabrice Leroux

Universitée Blaise Pascal, Aubière, France

•  Nano/Microporous Materials: Nanostructured Layered Double Hydroxides

Chengdu Liang

Oak Ridge National Laboratory, Oak Ridge, TN, USA

•  Nano/Microporous Materials: Mesoporous and Surface-Functionalized Mesoporous Carbon

Zhien Lin

University of California-Riverside, Riverside, CA, USA

•  Nano/Microporous Materials: Crystalline Metal-Chalcogenide Superlattices

Simon Lotz

University of Pretoria, Pretoria, South Africa

•  Supramolecular Materials: Metal-Quinonoid Complexes

Fushen Lu

Clemson University, Clemson, SC, USA

•  Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

Tong-Bu Lu

Sun Yat-Sen University, Guangzhou, China

•  Nano/Microporous Materials: Transition Metal Cyanides

Zhen Ma

Oak Ridge National Laboratory, Oak Ridge, TN, USA

•  Gold Nanoparticles as Chemical Catalysts

Ramón Martínez-Máñez

Universidad Politécnica de Valencia, Valencia, Spain

•  Biomimetic Chemistry of Hybrid Materials

•  Functional Supramolecular Hybrid Materials

Richard T. Mayes

University of Tennessee, Knoxville, TN, USA

•  Nanostructured Catalysts: Controlling Single-Site Composition

Mark S. Meier

University of Kentucky, Lexington, KY, USA

•  Carbon Nanotubes, Multi-Walled

Mohammed J. Meziani

Clemson University, Clemson, SC, USA

•  Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

Stuart R. Miller

University of St. Andrews, St. Andrews, UK

•  Nanoporous Metal Phosphonates

Svetlana Mintova

Université de Haute Alsace, Mulhouse, France

•  Nano/Microporous Materials: Hydrothermal Synthesis of Zeolites

Joshua T. Moore

Tennessee State University, Nashville, TN, USA

•  Semiconductor/Ceramic Nanocomposites: Synthesis, Characterization, and Properties

Charles J. O’Connor

University of New Orleans, New Orleans, LA, USA

•  Liquid-Phase Synthesis of Inorganic Nanoparticles

Yuval Ofir

University of Massachusetts Amherst, Amherst, MA, USA

•  Gold Nanoparticles: Monolayer-Protected Scaffolds and Building Blocks

Steven H. Overbury

Oak Ridge National Laboratory, Oak Ridge, TN, USA

•  Gold Nanoparticles as Chemical Catalysts

Rudolf Pfeiffer

Universität Wien, Vienna, Austria

•  Carbon Nanotubes, Single-Walled: Functionalization by Intercalation

Thomas Pichler

Universität Wien, Vienna, Austria and IFWDresden, Dresden, Germany

•  Carbon Nanotubes, Single-Walled: Functionalization by Intercalation

Nand Kishore Prasad

IT-BHU, Varanasi, India

•  Biomedical Applications of Magnetic Nanoparticles

Vanessa Prévot

Université Blaise Pascal, Aubiere, France

•  Nano/Microporous Materials: Nanostructured Layered Double Hydroxides

Eric Prouzet

University of Waterloo, Waterloo, ON, Canada

•  Inorganic Nanomaterials Synthesis Using Liquid Crystals

Merlyn X. Pulikkathara

Rice University, Houston, TX, USA

•  Carbon Nanotubes: Fluorinated Derivatives

Dali Qian

University of Kentucky, Lexington, KY, USA

•  Carbon Nanotubes, Multi-Walled

Maja Remškar

Jožef Stefan Institute, Ljubljana, Slovenia

•  Inorganic Nanotubes

José A. Rodriguez

Brookhaven National Laboratory, Upton, NY, USA

•  Metal Oxide Nanoparticles

John A. Rogers

University of Illinois at Urbana-Champaign, Urbana, IL, USA

•  Inorganic Semiconductor Nanomaterials for High-Performance Flexible Electronics

Vincent M. Rotello

University of Massachusetts Amherst, Amherst, MA, USA

•  Gold Nanoparticles: Monolayer-Protected Scaffolds and Building Blocks

Knut Rurack

Bundesanstalt für Materialforschung und -priifung (BAM), Berlin, Germany

•  Biomimetic Chemistry of Hybrid Materials

•  Functional Supramolecular Hybrid Materials

Ryan D. Rutledge

Vanderbilt University, Nashville, TN, USA

•  Biomineralization: Peptide-Mediated Synthesis of Materials

Marie-Louise Saboungi

CNRS-Université d’Orléans, Orleans, France

•  Nanocomposite Materials: Semiconductors in Zeolites

Alexander M. Seifalian

University College London, London, UK and Royal Free Hampstead NHS Trust Hospital, London, UK

•  Nanocomposite Materials: Polyhedral Silsesquioxanes

Hidetsugu Shiozawa

University of Surrey, Guildford, UK and IFW Dresden, Dresden, Germany

•  Carbon Nanotubes, Single-Walled: Functionalization by Intercalation

Sudhanshu Srivastava

University of Massachusetts Amherst, Amherst, MA, USA

•  Gold Nanoparticles: Monolayer-Protected Scaffolds and Building Blocks

Marinella Striccoli

Italian National Research Council—CNR, Istituto per i Processi Chimici e fisici, Bari, Italy

•  Inorganic Nanocrystals: Patterning and Assembling

Shouheng Sun

Brown University, Providence, RI, USA

•  Monodisperse Magnetic Nanoparticles: Chemical Synthesis and Surface Modification

Ya-Ping Sun

Clemson University, Clemson, SC, USA

•  Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

Dwight A. Sweigart

Brown University, Providence, RI, USA

•  Supramolecular Materials: Metal-Quinonoid Complexes

Andreas Taubert

University of Potsdam, Golm, Germany

•  Inorganic Nanomaterials Synthesis Using Ionic Liquids

Valentin Valtchev

Université de Haute Alsace, Mulhouse, France

•  Nano/Microporous Materials: Hydrothermal Synthesis of Zeolites

Sébastien Vasseur

Université de Bordeaux, Bordeaux, France

•  Biomedical Applications of Magnetic Nanoparticles

Lucia Monica Veca

Clemson University, Clemson, SC, USA

•  Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

Javier Vela

Los Alamos National Laboratory, Los Alamos, NM, USA

•  Semiconductor Nanocrystals: Doped Compositions

Michael J.Wagner

George Washington University, Washington, DC, USA

•  Inorganic Nanomaterials Synthesis Using Alkalide Reduction

WeiWang

Clemson University, Clemson, SC, USA

•  Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

Xin Wang

Clemson University, Clemson, SC, USA

•  Carbon Nanotubes and Nanocomposites for Electrical and Thermal Applications

Xiqing Wang

Oak Ridge National Laboratory, Oak Ridge, TN, USA

•  Nano/Microporous Materials: Mesoporous and Surface-Functionalized Mesoporous Carbon

Matthew C. Weisenberger

University of Kentucky, Lexington, KY, USA

•  Carbon Nanotubes, Multi-Walled

David W.Wright

Vanderbilt University, Nashville, TN, USA

•  Biomineralization: Peptide-Mediated Synthesis of Materials

Paul A. Wright

University of St. Andrews, St. Andrews, UK

•  Nanoporous Metal Phosphonates

Jin Xie

Brown University, Providence, RI, USA

•  Monodisperse Magnetic Nanoparticles: Chemical Synthesis and Surface Modification

Shangfeng Yang

Leibniz-Institute for Solid State and Materials Research (IFW) Dresden, Dresden, Germany and University of Science and Technology of China, Hefei, China

•  Endohedral Fullerenes

Baodian Yao

Fudan University, Shanghai, China

•  Periodic Mesoporous Organosilicas

Wei-Tang Yao

University of Science and Technology of China, Hefei, People’s Republic of China

•  Inorganic Nanobelt Materials

Paul E. Yeary

Alice Lloyd College, Pippa Passes, KY, USA

•  Carbon Nanotubes, Multi-Walled

Shu-Hong Yu

University of Science and Technology of China, Hefei, People’s Republic of China

•  Biomineralization: Self-Assembly Processes

•  Inorganic Nanobelt Materials

Dongyuan Zhao

Fudan University, Shanghai, China

•  Periodic Mesoporous Organosilicas

Zhiping Zheng

University of Arizona, Tucson, AZ, USA

•  Molecular and Supramolecular Arrays of the [Re6(μ3-Se)8]2+ Core-Containing Clusters

Hong-Cai Zhou

Miami University, Oxford, OH, USA

•  Nano/Microporous Materials: Hydrogen-Storage Materials

•  Nano/Microporous Materials: Transition Metal Cyanides

Pavel Zrazhevskiy

University of Washington, Seattle, WA, USA

•  Multicolor Quantum Dots in Molecular Profiling of Cancer Cells and Tissues

Series Preface

The success of the Encyclopedia of Inorganic Chemistry (EIC) has been very gratifying to the editors. We feel, however, that not everyone will necessarily need access to all ten volumes of the EIC. Some readers may prefer to have more concise thematic volumes, targeted to their specific area of interest. This idea has encouraged us to produce a series of EIC Books, focusing on topics of current interest. These will appear on a regular basis from now on, and will feature the leading scholars in their fields. Like the Encyclopedia, we hope that EIC Books will give both the starting research student and the confirmed research worker a critical distillation of the leading concepts, and provide a structured entry into the fields covered.

Computer literature searches have become so easy that one could be led into thinking that the problem of efficient access to chemical knowledge is now solved. In fact, these searches often produce such a vast mass of material that the reader is overwhelmed. As Henry Kissinger has remarked, the end result is often a shrinking of one's perspective. In the EIC Books we hope readers will find an expanding perspective to furnish ideas for research, and a solid, up-to-date digest of current knowledge to provide a basis for instructors and lecturers.

I take this opportunity of thanking R. Bruce King, who pioneered the Encyclopedia of Inorganic Chemistry, my fellow editors, as well as the Wiley personnel and, most particularly, the authors of the articles for the tremendous effort required to produce such a series on time. I hope that EIC Books will allow readers to benefit in a more timely way from the insight of the authors and thus contribute to the advance of the field as a whole.

Robert H. CrabtreeYale UniversityDepartment of Chemistry

April 2007

Volume Preface

Inorganic chemists have contributed greatly to the growing understanding of nanoscale materials by developing creative methods to synthesize, characterize, manipulate, and utilize nanomaterial substances. The second edition (2005) of the Encyclopedia of Inorganic Chemistry (EIC) included seven overviews of nanoscale science related to inorganic and bioinorganic chemistry, covering the period 1994–2004. Topics covered at that time were biomimetic approaches to nanocluster synthesis, metallic materials deposition from metal-organic precursors, porous inorganic materials, self-assembled inorganic architectures, semiconductor nanocrystal quantum dots, sol-gel encapsulated nanoparticles, and the synthesis and organization of metal nanoparticles.

Rapid growth in both the depth and breadth of nanomaterials research requires timely review of this important field of chemistry. Nanomaterials: Inorganic and Bioinorganic Perspectives is an EIC Book that provides, in a single volume, forty-four topical overviews of recent advances in nanomaterials research, of interest to inorganic or bioinorganic chemists. Topics reviewed include new areas of research such as nanobelt materials, areas experiencing renewed interest such as hydrogen storage materials, as well as comprehensive coverage of recent developments in biologically-templated or biomimetic nanoscale materials, fullerene and nanotube chemistry, semiconductor nanoparticles, metal nanoparticles, supramolecular and microporous materials, magnetic nanoparticles, and nanoscale synthesis strategies or materials fabrication.

Contributors were asked to write reviews emphasizing recent literature, published from 2004–present, showing how the explicit or implicit application of inorganic chemistry concepts and methods has advanced nanomaterials science. Whilst nanomaterials with novel compositions and/or shapes continue to be discovered, there is also growing interest in the design of more complex nanoscale materials, such as composites, porous solids, and two- or three-dimensional architectures, to mimic structures observed in nature or to exhibit properties required for specific applications. We hope that inorganic and bioinorganic chemists entering this field of research will find this book to be a valuable starting point for their own creative thinking.

Charles M. Lukehart

Robert A. Scott

Vanderbilt University

University of Georgia

Department of Chemistry

Department of Chemistry

October 2008

Biologically Templated Nanostructure Assemblies

Silke S. Behrens

Institute of Technical Chemistry, Karlsruhe, Germany

1 INTRODUCTION

Biomolecular components have been optimized during evolution with respect to their specific molecular recognition capabilities as well as their functionality for distinct biochemical transformations and translocations. Nature is able to synthesize a plethora of well-organized, inorganic materials.1–3 Organisms have evolved the ability to direct the synthesis and assembly of crystalline inorganic materials by uptake of the necessary precursors from the local environment followed by incorporation into functional structures under strict biological control. Structure and function have been cooptimized phylogenetically. Material synthesis by living systems is inherently different from synthetic material synthesis. Although synthetic materials may be self-assembled using equilibrium-regulated processes, nature has evolved a wide variety of nonequilibrium-based strategies for directing the assembly and organization of materials at the nano and molecular scale. Natural material synthesis occurs under environmentally benign conditions with precise control over chemical composition and phase. A well-known example is magnetotactic bacteria that form magnetite crystals, with both size and morphology dependent on the type of bacteria. These biogenic magnetite particles exhibit not only a specific size and morphology but also a very narrow size distribution and a diameter in the range of 40–120 nm with a high magnetic moment. Because magnetite particles from inorganic synthesis neither offer a comparable size distribution nor such a control of crystal morphology, techniques have been developed to isolate magnetosomes (i.e., magnetite crystals surrounded by a membrane) from bacteria.4

However, natural material synthesis is usually limited to inorganic materials, such as magnetite or calcium carbonate. Hence, the knowledge of biological concepts, functions, and design features has recently been exploited for the production of new, technologically important, inorganic materials that have no isomorphous complement in nature.5–12 At the interface between chemistry, biology, and materials science, the variety of biological molecules, assemblies, and living organisms offers species-specific details not provided by man-made templates. In addition to the richness of naturally occurring templates, the powerful techniques developed by life sciences are becoming a promising tool for engineering approaches toward nanotechnology. The following review is focused on recent advances in the fabrication of inorganic nanomaterials taking advantage of biological assembly processes and bioassemblies.

2 CHEMICAL PROCEDURES FOR BIOTEMPLATED NANOSTRUCTURES

One major challenge in manufacturing nanostructures by biotemplating has been the need to either modify traditional methodologies derived from chemistry or microelectronics, or to develop new synthetic pathways, in order to make the material synthesis compatible with the relatively labile biotemplates.

Over the last decade, several groups have investigated electroless plating technologies for use with biotemplates instead of inorganic templates. Electroless deposition is derived from metallurgy and has various applications in nano- and microtechnology.13,14 This technology allows the production of high-quality ultrathin films with highresolution patterns. Electroless metal plating is affected by the deposition of metals or alloys by chemical reduction of metal cations in solution through a selective process that takes place heterogeneously on a catalytic surface. Therefore, a noncatalytic surface, such as the surface of a biological nonconductor, has to be activated before the metallization process. A typical electroless plating bath comprises an aqueous solution containing metal ions (i.e., metal source) bound by complexation with a ligand chelator, a buffer to control the pH value, and a reductant. Electroless deposition techniques are usually applied to generate metal nanostructures, such as Ag, Au, Pd, Pt, or alloys.

For the processing of bioorganic templates, certain modifications of the electroless plating technology have to be attempted (Figure 1). First, the deposition conditions need to be compatible with biological substrates, e.g., in terms of the pH value (near pH 7), the absence of reagents affecting the biological material, and mild reduction temperatures. Secondly, a certain stability of the bioorganic template toward chemical and thermal treatments is required. Thirdly, the deposition process has to be highly selective, i.e., the deposition should take place heterogeneously only on the surface of the biotemplate and not in the bulk solution.

Electroless plating procedures of biotemplates typically involve two steps: surface activation of the noncatalytic biotemplate surface and autocatalytic metal growth. Activation can be performed by forming specific complexes of the metal ion precursor with the surface functionalities of the biostructure. Such biomolecule/metal ion complexes may be formed with the heteroatoms in the side chains of amino acid residues for biotemplates based on proteins or with the heteroatoms of the deoxyribonucleic acid (DNA) bases. Imidazole heterocycles, for example, which are present in the side chains of histidines or the DNA bases, guanine and adenine, have been demonstrated to be an important structural motif during the initial binding of metal ions to biostructures and in the formation of the initial metal nuclei and, thus, promote biotemplate activation.15,16 Recently, biotemplates have been genetically engineered to expose metal-ion-specific surface functionalities. Alternatively to metal ion/biomolecule complexes, the biotemplate may be activated by binding of preformed catalytic metal particles, usually Au nanoparticles. In a second step, autocatalytic, surface-controlled metal growth is performed by exposing the activated biotemplate to a mild reducing bath. Common reductants used to deposit metals on biotemplates are dimethylamine borane (DMAB) or NaBH4. This autocatalytic deposition process may be affected or stopped by diluting the reaction medium or by washing. Besides the nature of the applied reducing agent and the metal ion precursor, the quality of biotemplated metal structures is highly dependent on the reaction parameters,17 i.e., the pH value, the absolute and relative concentration of the chemical reagents and the biotemplate, or the reaction temperature. The metallization of biostructures by electroless deposition has been applied, for example, for the preparation of nanowires, using protein nanotubes such as microtubules15,18 or DNA.19

Figure 1 Procedure for electroless plating of biostructures

For generating nonmetallic nanostructures, alternative chemical procedures have to be applied. These procedures are typically based on precipitation by a controlled supersaturation of the biomineralization solution. Nanostructures of metal chalcogenides, e.g., iron oxide or cadmium selenide, can be obtained by such a procedure. Supersaturation of the biomineralization solution, for example, may be controlled in situ by slowly diffusing a gas, e.g., oxygen, H2S, or H2Se, into a solution containing the metal ion precursor. FeOOH coatings, for example, could be obtained in situ by oxidizing a Fe2+ solution in air.20 Moreover, precipitation may be controlled by adjusting the pH value. Again these biomineralization processes for the generation of nanostructures are based on surface chemical interaction and have to be highly specific to the surface of the bioorganic template, and therefore the proper adjustment of reaction parameters is a prerequisite.

Alternative to direct deposition of inorganic matter on biomaterials, the highly specific molecular recognition capabilities of biomolecules conjugated to preformed inorganic building blocks can be exploited for the bottom-up construction of multiplex-ordered architectures. Typically, the metal or semiconductor nanoparticles have been first prepared by conventional chemical synthesis in solution and were then linked to biomolecules exhibiting specific recognition properties, such as proteins (e.g., antibodies) or DNA. Biomolecules can be bound to the surface of nanoparticles by ligand exchange reactions. However, the synthesis of stoichiometrically defined conjugates is a challenge, and further ligand exchange reactions may prevent the formation of stable bioconjugates and efficient supramolecular assembly. Thus, the development of ligands bearing functional groups, which tightly bind to the surface of nanoparticles, has been the focus of research. Alternatively, the ligands can be covalently attached to an intermediate, cross-linked organic (e.g., polymer) or inorganic (e.g., silica) layer. Such conjugates are stable as long as covalent bonds have to be broken to disintegrate them. Moreover, for superstructure assembly the biological functionality of the biomolecule has to be retained after conjugation to nanoparticles.

In the following sections the above-mentioned chemical procedures are discussed for the generation of nanostructures by applying biological assembly processes and bioassembly templates.

3 BIOTEMPLATING

The use of biomolecules for synthesis of nanostructured materials focuses on different aspects. First, methods based on biomolecule assemblies take advantage of the characteristic nanometer dimensions of the biological specimen. Biomolecular components have typical size dimensions from the lower nanometer size range up to several micrometers. They represent spatially confined environments with a defined structural topology for the surface-controlled deposition of the inorganic material. Biomolecular components reveal specific patterns of surface functionalities, e.g., amino acid residues or the bases of nucleic acids that are able to bind metal ions or nanoparticles by electrostatic interaction or formation of metal-ligand complexes. Moreover, the highly specific molecular recognition capabilities of biomolecules conjugated to preformed inorganic building blocks can be exploited for the bottom-up construction of multiplex-ordered architectures. Till now, a variety of different biological systems and components has been used to direct the nucleation, deposition, and assembly of inorganic materials into defined micro- and nanostructures.

3.1 Protein- and Peptide-Based Systems

Proteins were shown to template nanowires and nanoparticles. They reveal specific recognition properties (e.g., antibody–antigen or biotin–avidin interaction) and catalytic functions (e.g., enzymes). They are able to form superstructures in the nanometer size range with defined morphology. Moreover, different proteins exhibit motor functions, and therefore motility on surfaces. Proteins from bones, shells, diatomers, and magnetic bacteria21 can nucleate crystalline inorganic materials with precise control of chemical composition and phase. These various functions of proteins, together with the possibility to modify them by chemical means and by genetic engineering, provide superior properties for the bottom-up synthesis of nanostructures. Protein–nanomaterial interactions have been exploited to form defined superstructures, whereas proteins were applied to organize nanomaterials and nanomaterials to organize proteins.22

3.1.1 Cellular Components

A variety of components in the cell consist of highly ordered protein structures that are responsible for multiple essential functions of the cell.23 A plethora of these protein assemblies have been exploited as a powerful tool for the generation, organization, and transport of nanomaterials:

Cytoskeletal Filamentous Assemblies. Microtubules (MTs), for example, are cytoskeletal protein assemblies ubiquitously present in eukaryotic cells.24 As part of the cytoskeleton, they are important structures for both cellular architecture and motility. In vitro, microtubules can be obtained from tubulin by a self-assembly process in the presence of the cofactors Mg2+ ions and GTP (guanosine-5'-triphosphate) at physiological pH, ionic strength, and temperature (Figure 2a). MTs are built by protofilaments consisting of longitudinally connected αβ tubulin heterodimers with a strict α–β alternation. Tubulin molecules exhibit chemically functional surfaces with defined patterns of amino acid side chains that provide a wide variety of active sites for derivatization, especially, for nucleation, organization, and binding metal particles. MTs are hollow cylinders with outer diameters of 25 nm and lengths of several micrometers, and therefore present a template with high lengths-to-width aspect ratio. MTs have been used to template the formation of various metal nanoparticles and nanowires.25 Ag nanoparticles of 5.2 nm, for example, could be nucleated on MT surfaces using a NaBH4 reduction bath (Figure 2c).26 The MT attached nanoparticles could then be further enlarged applying hydroquinone and Ag+ ions, a reaction widely studied in connection with photographic procedures. Even completely continuous Ag nanowires could be generated by using MTs and a similar chemical method (Figure 2d). In this case, MTs were initially incubated with silver nitrate, and hydroquinone was then added rapidly. The reaction could be stopped by adding an excess of S2O32−, which complexes the remaining silver ions in solution. The mean diameter of the silver wires measured from transmission electron microscopy (TEM) images after 2.5 min of reaction was ~40 nm and it grew to ~77 nm after 7 min. The wires agglomerated into extended networks precipitating after several minutes. Metal oxide coatings, e.g., FeOOH coatings of different morphologies could be obtained by biomimetic mineralization of MTs.20 Supersaturation of the biomineralization solution was generated in situ by oxidizing a Fe2+ solution in air. The thickness and crystallinity of the FeOOH coating could be attenuated by altering the reaction conditions. When tubulin subunits were labeled by CdSe nanorods they were still able to self-assemble into MTs, thereby demonstrating that the functionality of the protein was preserved after particle binding.27,28 The high brilliance and photostability of such semiconductor nanocrystals enable long-term on-line monitoring of biological processes (see Multicolor Quantum Dots in Molecular Profiling of Cancer Cells and Tissues). Kumara et al. have used bioengineered flagellin protein for templating of nanostructures. Peptide loops of bacterial flagellin protein were bioengineered to form bionanotubes with evenly spaced binding sites for metal ions.29 Six different types of metal ions were complexed to the modified peptide loops. The careful reduction with NaBH4 or hydroquinone was shown to form metal-flagellin nanoparticle arrays and nanowires. Flagella are filamentous structures attached to cells and are used for cell motility. Flaggella of eukaryotes consist of complex arrangements of several MTs, whereas bacterial flagella represent smaller and simpler structures.

Figure 2 (a) Tubulin heterodimers self-assemble into a variety of polymorphs such as microtubules or spirals/rings consisting of differently arranged protofilaments with a strict alternation of α- and β-tubulin monomers. By electroless silver plating complex nanoarchitectures, e.g., particle arrays with various geometry (b,c) (From Behrens et al.30 © Wiley-VCH Verlag & Co. KGaA. Reproduced with permission) or continuous nanowires (c,d). (From Behrens et al.26 Reproduced with permission of the American Chemical Society)

The intracellular transport of materials (e.g., vesicles, chromosomes) by kinesin and dynein motor protein along cytoskeletal networks composed of MT filaments has been well studied.31 Triggered by adenosine triphosphate (ATP) fuel, conventional kinesin moves along MT filaments in 8-nm steps, by alternating between two conformational states. The polymeric nature of the MT structure has been exploited to assemble and organize CdSe quantum dots into linear composite chains, which could then be actively transported on synthetic surfaces by kinesin motor protein.32

In addition to MTs, tubulin is also able to self-assemble into a variety of polymorphs: tubules, sheets, ribbons, or spirals/rings all consisting of differently arranged protofilaments with a strict alternation of α- and β-tubulin monomers.33 In the presence of Ca2+ ions, for example, tubulin assembles in cell-free environment into rings and spirals instead of MTs (Figure 2a). Ringlike tubulin assemblies provide a tool to control the deposition of Ag nanoparticles into spiral-shaped arrays along the backbone of the spiral-shaped biostructure (Figure 2b).30 The mean distance between the Ag particles of 7.31 ± 0.99 nm indicated the deposition of one Ag particle per tubulin dimer. Clearly, the growth of nanoparticles on these tubulin structures depends critically on the proper choice of reducing agent and the relative and absolute educt concentration. The interesting features in nanoscale ring systems are the interference phenomena of the electron wave function observed for electrons in nanosized ring systems, the Aharonov–Bohm effect.34 Polymeric tubulin systems exhibit various morphologies and geometries based on the same monomeric units, and thus, demonstrate the potential of bioassemblies for the generation of different nanomaterials.

Much like MTs, actin filaments, i.e., microfilaments are part of the cytoskeleton in eukaryotic cells and represent important structures in view of cellular architecture and motility. Actin filaments, F-actin, are threadlike protein polymers with a diameter of 7–9 nm and a helical monomer arrangement. F-actin self-assembles from globular-actin (G-actin) monomers in the presence of ATP and Mg2+, K+, or Na+ ions. Together with its motor protein myosin, F-actin is responsible for cellular motility, e.g., the contraction of mussels and the transport of organelles, a process triggered by ATP fuel. Compared to MTs, actin filaments are thinner, more flexible, and usually shorter. Recently, F-actin has been exploited by Willner et al. as a template for fabricating metallic nanowires with motility functions.35 In this context, G-actin monomers were modified by single Au nanoparticles (1.4 nm) and assembled to F-actin. The Au nanoparticles were then enlarged by catalytic reduction of AuCl4– to form a continuous Au nanowire of 80–100 nm × 1–2 μm exhibiting conductivity features similar to bulk Au. For movable nanowires, assembly of NP-functionalized G-actin was followed by polymerization of unmodified G-actin at the ends of the filaments. The reduction of AuCl4– resulted in the formation of an Au nanowire with two base-actin filaments at its end. These actin/Au nanowire/actin nanostructures moved at 250 nm s–1 on a myosin functionalized surface triggered by ATP fuel.

Cellular Envelopes. Regularly arrayed two-dimensional protein structures are found in cell membranes, such as the surface layers (S-layers) of bacteria and archae. They represent interesting templates in view of the formation of two-dimensional metal arrays.36 S-layers are crystalline protein sheets with lattice constants of 5–30 nm and p2, p3, p4, or p6 symmetry found in the cell envelope of bacteria and archae. They display several pores and gaps per unit cell which enable the penetration of macromolecules, particles, or metal ions (Figure 3). Wahl et al., for example, have demonstrated the deposition of Pd clusters on S-layers isolated from Sporosarcina ureae.37 The treatment of the S-layer template with palladium complexes, K2PdCl4, led to the development of Pd cluster arrays. Electron microscopy and image processing revealed that the Pd clusters were preferably located in the porous regions of the protein lattice providing sufficient cluster–protein interaction to stabilize the cluster position. By exposing 5-nm-sized Au nanoparticles to the hexagonally packed intermediate (HPI) layer of Deinococcus radiodurans, long-range ordered two-dimensional particle arrays exhibiting a honey-comb structure with hexagonal symmetry were obtained.38 The citrate-capped Au nanoparticles were shown to adsorb at every second vertex point between adjacent hexameric units, and not to the 2.2-nm-sized central pores. If particle-particle repulsion was reduced by increasing the ionic strength with NaCl, nearly every vertex point was occupied by Au nanoparticles. As a conclusion, interaction of the negatively charged Au nanoparticles and the positively charged groups on the HPI layer on one side as well as electrostatic repulsion between the Au nanoparticles on the other side controlled the formation of the close-packed hexagonally ordered particle arrays with 18-nm interparticle spacing. This hypothesis was further supported by experiments using neutral or positively charged control experiments. Furthermore, it could be shown that ordered arrays were preferably formed on the hydrophilic extracellular phase of the HPI layer, whereas on the hydrophobic intracellular phase no long-range order was observed. In other work by the same group, S-layers from D. radiodurans (p6 rotational symmetry, lattice constant 18 nm) were compared with S-layers from Sulfolobus acidocaldarius (p3 symmetry, lattice constant 22 nm) for their ability to biotemplate ordered arrays of inorganic nanoparticles.39 The assembly of citrate-capped Au nanoparticles and hydrophilic CdSe/ZnS core/shell quantum dots was investigated. The degree of two-dimensional ordering was quantitatively evaluated by Fourier transform (FT) and pair correlation function (PCF) analysis. Through TEM studies together with FT/PCF analyses, it could be shown that the lattice spacing and the morphology of the particle arrays could be changed by using different S-layer templates. Figure 3 displays the TEM images and the corresponding fast Fourier transform (FFT) power spectra of hexagonally packed intermediate (HPI) S-layers and Sulfolobus acidocaldarius (SAS) S-layers with citrate-stabilized, 5-nm Au nanoparticles and 7-carboxy-1-heptanethiol-capped CdSe/ZnS core/shell quantum dots. The ordered patterns emerging on the extracellular (H1) phase exhibited a sixfold symmetry and a mean-nearest neighbor distance of 18.3 and 18.4 nm for the Au particles and the quantum dots, respectively, commensurate with the lattice constant of the HPI S-layer. Adsorption on the intracellular (H2) phase resulted in less ordered patterns from random particle adsorption to any of the six vertex positions. For SAS S-layers, a nearest neighbor distance of 21.6 nm was measured for the Au nanoparticles and the quantum dots, which is in agreement with the lattice constant of the SAS S-layer. Interestingly, in this case ordered patterns were also observed for the S1 phase. Moreover, S-layers from D. radiodurans and S. acidocaldarius were investigated for their potential to assemble dendrimer-encapsulated Pt nanoparticles.40 These Pt nanoparticles were prepared in aqueous solution using K2PtCl4, hydrophilic generation 4 PMAM-OH dendrimers, and NaBH4. For nanoparticle assembly, the S-layers were first adsorbed on a carbon-coated TEM grid and then floated on a drop of the Pt nanoparticle containing solution. Recently, ordered Au nanoparticle arrays assembled by S-layer templates were used as a nanolithographic hard-mask pattern in an inductively coupled plasma etching process to fabricate silicon nanopillars.41

Alternatively to S-layers, cysteine mutants of purple membrane, a two-dimensional array of lipids and bacteriorhodopsin, were applied for the patterning of 2.6-nm-sized Au nanoparticles bearing a thiol-reactive maleimide group.42 Although the formed assemblies lacked long-range order, the interparticle distances of 4-7 nm were commensurate with the unit cell dimensions of the purple membrane template. Bacteriorhodopsin mutants, displaying histidine tags, allowed the patterning of 4-nm-sized Ag2S nanoparticles by in situ reaction with Ag+ ions and thioacetamide.

Figure 3 Scheme comparing the structure and symmetry of S-layers from Deinococcus radiodurans (HPI, p6 rotational symmetry) and Sulfolobus acidocaldarius (SAS, p3 symmetry). TEM images and corresponding FFT power spectra of the HPI and SAS S-layers with citrate-stabilized, 5-nm Au nanoparticles and 7-carboxy-1-heptanethiol-capped CdSe/ZnS core/shell quantum dots. H1 and H2 represent the HPI intracellular and extracellular phase, respectively, and S1 and S2 represent the SAS intracellular and extracellular phase, respectively. (From Mark et al.39 Reproduced with permission of the American Chemical Society)

Such bio-inspired, two-dimensionally ordered structures will be interesting for future investigations of the collective optoelectronic/physical properties; e.g., they could display enhanced optical nonlinearity effects. They represent a potential synthetic pathway for the future development of novel types of surfaces for electronic, optical, and sensor applications, or for magnetic data storage.

Ferritin. Pioneering work on the use of biotemplates was based on the iron storage protein ferritin. Ferritin consists of a 6-nm-sized central core of hydrated iron oxide(III) surrounded by a protein shell. By removing the ferrihydrite core through reductive dissolution, an 8-nm-sized empty protein capsid with small channels, termed apo-ferritin, is obtained. Apo-ferritin is very stable and robust and allows constraint material synthesis. In recent work, catalytic metal clusters have been encapsulated in the apo-ferritin cavity. The monodisperse, spherical, and zero-valent Pd clusters were synthesized by the in situ chemical reduction of Pd2+ ions, which were concentrated in the interior of the protein cage. The catalytic activity of the as-prepared Pd-ferritin catalyst was evaluated for the hydrogenation of olefins. By pore blocking with TbIII, it could be demonstrated that the anionic threefold hydrophilic channels were the pathway for substrates during the catalytic reaction. Using the Pd-apo-ferritin catalyst for the hydrogenation of several substrates, the order of the substrate size roughly correlated with the experimental turn over frequency (TOF) data obtained and, thus, led to a certain degree of size selectivity. In other work by Kim et al., the ferritin-based fabrication of hollow transition-metal oxide nanoparticles has been reported.43 Apo-ferritin was first loaded with 200 Co2+ ions and exposed to H2O2 to nucleate 1.8-nm Co3O4 grains at specific sites at the interior surface of the capsid. Upon further addition of Co2+ ions and H2O2, hollow cobalt oxide nanoparticles complementary to the protein shell were formed.

3.2 Microorganism Templates

3.2.1 Viruses as Building Blocks for Inorganic Materials

In material science, viruses have been widely applied as scaffolds for the chemical synthesis of inorganic materials.44,45 The size and shape of viruses, and the number and nature of the functional groups on their surface, are precisely defined. The protein coat of viruses comprise hundred to thousands of protein subunits that self-assemble into cagelike or rodlike compartments, which enclose the viral nucleic acid. The protein capsid provides a rigid container protecting and delivering the viral nucleic acids on its passage from its host cell to other cells. Viruses occur in a wide range of sizes and morphologies and many examples of polymorphic forms exist. Moreover, the properties of viruses can be tailored with regard to material deposition by changing the nucleic acid sequence of the viral genome. Most studies of material synthesis apply viruses without enveloping membranes. The employed viruses with the exception of bacteriophages mainly comprise nonenveloped plant viruses such as tobacco mosaic virus (TMV), cowpea mosaic virus (CPMV), or cowpea chlorotic mottle virus (CCMV). They can be isolated in large quantities and lack pathogenicity toward humans. Viruses can be modified by means of molecular-biology techniques on the level of the genetic code rather than by chemical modification.

A common viral template that has been studied for its use in material synthesis during the last decade is the TMV. The TMV consists of a hollow tube comprising the viral ribonucleic acid (RNA), with an outer and inner diameter of 18 and 4 nm, respectively, and a length in the range of 300 nm. Native TMVs were shown to induce the nucleation of metal nanoparticles selectively either on the exterior surface or in the central channel (or both), depending on the conditions of template activation and electroless metal deposition.46 A range of TMV-metal composites, comprising metal nanoparticle arrays and metallic nanowires, has been prepared. When the TMV was activated, e.g., with Pd2+ ions, and then metallized with a nickel-phosphinate bath, Ni clusters grew inside the central channel of the template, whereas, when TMV suspensions in phosphate buffer were employed, Ni clusters grew on the exterior TMV surface. Moreover, the viral RNA allowed to couple 6-nm Au nanoparticles exclusively to the ends of the 300-nm-long viral tubes.47 Their size could be enhanced to several tens of nanometers by electroless Au deposition, resulting in Au/virus/Au dumbbells. It was suggested that the Au nanoparticles specifically interacted with the heterocyclic aromatic bases of the viral RNA. By genetic engineering, Lee et al. have improved TMV templates for metal deposition by inserting two surface-exposed cysteine residues as a ligand for covalent thiol-metal binding.48 Metallization of the mutant TMV was demonstrated by depositing discrete Au, Ag, and Pd nanoparticles by the in situ reduction with DMAB. Metal clusters were more densely deposited on the mutant TMV as compared to the unmodified, wild-type TMV template. Au particle deposition at higher pH values (pH 3.9–5.6) indicated that the metal deposition was primarily driven by the cysteine-derived thiol groups and not by electrostatic interaction. Recently, the TMV-supported synthesis of nanostructures has been expanded to bimetallic alloys of CoPt and FePt.49 The metallization process implied the sequential addition of the metal ion precursors, (NH4)2Co(SO4)2 and K2PtCl4, and the reducing agent, NaBH4, and exposure to ultrasonication. It was suggested that initially formed Pd nuclei catalyzed the Co2+ reduction to create the CoPt alloy. Ultrasonication was essential to boost the metal ion supply within the narrow TMV channel, thereby enhancing the growth of the deposited CoPt into nanowires of 15–105 nm length. Magnetic measurements indicated the ferromagnetic nature of the as-formed CoPt alloy by revealing a very small hysteresis loop with a coercivity of 25 Oe. Experiments with (NH4)2Fe(SO4)2 and K2PtCL4 also allowed the generation of long nanowires; however, the overall elemental composition suggested FePt3 and FePt. Coating of wild-type TMV and a mutant TMV, E50Q, with a thin silica layer was demonstrated by applying sol-gel processes.50 E50Q contains a glutamic acid to glutamine mutation at position 50 producing virus particles that assemble to lengths of approximately 1000 nm, which is beyond the usual 300 nm for native TMV. The deposition of silica on the viral surface was achieved by the base-catalyzed hydrolysis of tetraethoxysilane in methanol/water (50/50) at pH 8.8. Interestingly, the TMV-templated silica coatings enhanced the stability of the virus particles in methanol (100%) at conditions that would ordinarily disrupt the assembled particles. Resuspension of the silica-coated TMV in water, however, resulted in a breakup of the TMV structure over time.

Virus particles can be engineered to display peptides with specifically designed surface functions (see Biomineralization: Peptide-Mediated Synthesis of Materials). The most prominent surface display systems are based on bacteriophages. Material-specific peptides with preferential binding and control over nanoparticle nucleation have been identified by phage display techniques, using peptide libraries of ~109 random sequences.51 The protein sequences responsible for these attributes are gene linked, thereby allowing to produce exact genetic copies of the viral scaffold by infection into its bacterial host. Filamentous bacteriophages such as M13 bacteriophages were applied as biological building blocks owing to their controllable length and ability to display multiple peptides on the surface. The viral single-stranded DNA is encapsulated in a flexible cylinder of 930 × 6 nm, which is covered by 2700 copies of the major coat protein, PVIII, in a repeating helical array. About five copies each of PIII and PVI proteins are located at one end of the cylinder, and about 5 copies each of the PVII and PIX proteins at the other end. Belcher et al. have applied type 8 phage display systems to identify material-specific peptide sequences where the PVIII proteins were modified to display selected octapeptides. Computational analysis revealed a peptide distance of about 3 nm and above 20% incorporation. Mineralization of such CNNPMHQNC and SLTPLTTSHLRS modified phages with ZnS and CdS, respectively, has been demonstrated by Belcher et al.52 The viral template was incubated with the metal salt precursors at reduced temperature to ensure a uniform orientation of the peptides during nucleation. Wurzite ZnS and CdS nanocrystals (3–5 nm) were grown on the viral surface exhibiting a preferential crystallographic orientation on the substrate. The viral template could be removed by annealing at 350 °C to form single-crystal nanowires of CdS and ZnS. The nanowires were elongated along the [001] direction and exhibited wurtzite structure. The phage-directed material synthesis was also extended to produce ferromagnetic FePt53 and CoPt54 systems by implementing HNKHLPSTQPLA and EPGHDAVP sequences in M13 phages, respectively. After incubating the template, for example, with FeCl2 and H2PtCl6 and reducing with NaBH4, 4-nm-sized FePt nanoparticles were nucleated. Selected area electron diffraction indicated that the template induced the nucleation of a significant percentage of L10 phase FePt nanoparticles. This is remarkable as L10 FePt is not the kinetically favorable phase and usually occurs after annealing at high temperatures.55 Control experiments with bacteriophages with nonspecific peptide sequences lead to very little chemical ordering. Besides the M13 bacteriophages described earlier, the pure synthetically prepared dodecapeptides were also able to induce the nucleation of FePt particles exhibiting some chemical ordering. That biological approaches not only lead to new fundamental results but also represent an exciting potential for applications in various areas has recently been demonstrated by the rational design and assembly of nanoscale battery components.56 Co3O4 is one of a family of lithium-active compounds with an extremely large reversible storage capacity, which is interesting for applications in lithium ion batteries. To design electrodes of Co3O4 nanowires, a tetraglutamate pVIII M13 bacteriophage clone was engineered. Glutamate not only binds various positive metal ions through ion exchange but also reduces nonspecific Au nanoparticle binding. Owing to an increased negative charge, it interacts more favorably with the positively charged electrolyte polymer. Nanowires of uniformly distributed, highly crystalline, 2-3-nm-sized Co3O4 nanocrystals were formed through in situ reduction with NaBH4 and spontaneous oxidation. To evaluate the electrochemical performance, a Swadgelok cell with a positive electrode based on the Co3O4/M13 wires, a Li negative electrode, and a LiPF6 electrolyte was set up. A reversible capacity of 600-750mAh g-1 wasmeasured, i.e., about twice as much as in current carbon-based negative electrodes. Moreover, hybrid material electrodes consisting of Au and Co3O4 nanoparticles were generated by using a bifunctional virus template with two different peptide motifs. The virus-mediated hybrid composite generated an about 30% higher initial and reversible lithium storage capacity than the pure Co3O4 based system. The higher Li storage capacity may result from the formation of Au–Li intermetallic compounds or the conductive or catalytic effects of the Au nanoparticles on the reaction of Li with Co3O4. Moreover, on poly(ethyleneimine)/poly(acrylic acid) films two-dimensionally organized, flexible ensembles of Co3O4