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Dekker Encyclopedia of
Nanoscience and Nanotechnology

edited by

James A. Schwarz
Syracuse University, Syracuse, New York, U.S.A.

Cristian I. Contescu
Material Methods LLC, Newport Beach, California, U.S.A.

Karol Putyera
Shiva Technologies, Syracuse, New York, U.S.A.

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Volume 1:
Main image: Courtesy of Tommaso Baldacchini and John T. Fourkas.
Detail: Courtesy of Kay Severin.
Volume 2:
Main image: Courtesy of Hamidou Haidara.
Detail: Courtesy of Jean-Yves Raty.
Volume 3:
Main image: Courtesy of Tony Van Buuren and Jürgen M. Plitzko.
Detail: Courtesy of Kay Severin.
Volume 4:
Main image: Courtesy of A. I. Gusev and colleagues.
Detail: Courtesy of Jean-Yves Raty.
Volume 5:
Main image: Courtesy of Ioan Balint.
Detail: Courtesy of Lars-Oliver Essen.
ISBN: Print: 0-8247-5055-1
ISBN: Online: 0-8247-5046-2
ISBN: Combo: 0-8247-4797-6




Library of Congress Cataloging-in-Publication Data.
A catalog record of this book is available from the Library of Congress.
This book is printed on acid-free paper.
Marcel Dekker, Inc.
270 Madison Avenue, New York, NY 10016
tel: 212-696-9000; fax: 212-685-4540
Eastern Hemisphere Distribution
Marcel Dekker AG
Hutgasse 4, Postfach 812, CH-4001 Basel, Switzerland
tel: 41-61-260-6300; fax: 41-61-260-6333
World Wide Web
The publisher offers discounts on this book when ordered in bulk quantities. For more information, write to Special Sales/
Professional Marketing at the headquarters address above
Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.
Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical,
including photocopying, microfilming, and recording, or by a; ny information storage and retrieval system, without permission
in writing from the publisher.
Current printing (last digit):
10 9 8 7 6 5 4 3 2 1

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

James A. Schwarz
Syracuse University, Syracuse, New York, U.S.A.
Cristian I. Contescu
Material Methods LLC, Newport Beach, California, U.S.A.
Karol Putyera
Shiva Technologies, Syracuse, New York, U.S.A.

Editorial Advisory Board
Frank Armatis
Advanced Materials Technology Center,
3M Corporation, St. Paul, Minnesota, U.S.A.

D. Wayne Goodman
Department of Chemistry, Texas A&M University,
College Station, Texas, U.S.A.

R. Terry K. Baker
Catalytic Materials Ltd., Holliston, Massachusetts,

Elias Greenbaum
Chemical Sciences Division, Oak Ridge National
Laboratory, Oak Ridge, Tennessee, U.S.A.

Robert Birge
Department of Chemistry, University of Connecticut,
Storrs, Connecticut, U.S.A.

Hans-Joachim Güntherodt
Institut für Physik der Universität Basel,
Basel, Switzerland

Vijoleta Braach-Maksvytis
CSIRO Executive Management Council, Australian
Government, Lindfield, New South Wales, Australia

Norbert Hampp
Department of Chemistry, Philipps University,
Marburg, Germany

Gianfranco Cerofolini
ST Microelectronics, Milan, Italy

Tim Harper
CMP-Cientifica S.L., Madrid, Spain

Stephen Y. Chou
Department of Electrical Engineering, Princeton
University, Princeton, New Jersey, U.S.A.

Arthur Hubbard
Santa Barbara Science Project, Santa Barbara,
California, U.S.A.

Morinobu Endo
Department of Engineering, Shinshu University,
Nagano, Japan

Enrique Iglesia
Department of Chemical Engineering, University of
California, Berkeley, California, U.S.A.

Toshiaki Enoki
Department of Chemistry, Tokyo Institute of
Technology, Tokyo, Japan

Mietek Jaroniec
Department of Chemistry, Kent State University,
Kent, Ohio, U.S.A.

Gerhard Ertl
Department of Physical Chemistry, Fritz Haber
Institute of the Max Planck Society, Berlin, Germany

Andy Kaldor
ExxonMobil Research and Engineering, Annandale,
New Jersey, U.S.A.

Robert Glass
Lawrence Livermore National Laboratory,
Livermore, California, U.S.A.

Jürgen Kirschner
Max-Planck-Institut für Mikrostrukturphysik,
Halle, Germany

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Laszlo B. Kish
Department of Electrical Engineering,
Texas A&M University, College Station, Texas,

Debra R. Rolinson
Advanced Electrochemical Materials,
Naval Research Laboratory, Washington,
District of Columbia, U.S.A.

Kenneth Klabunde
Department of Chemistry, Kansas State University,
Manhattan, Kansas, U.S.A.

Jurgen Ruhe
Institute for Microsystem Technology, Albert-Ludwig
University, Frieberg, Germany

James Leckie
Department of Civil and Environmental
Engineering, School of Engineering,
Stanford University, Stanford, California,

Purnesh Seegopaul,
Umicore USA Inc., Hillsborough, New Jersey, U.S.A.
Stu Soled
ExxonMobil Research and Engineering, Annandale,
New Jersey, U.S.A.

Charles M. Lieber
Department of Chemistry and Chemical Biology,
Harvard University, Cambridge, Massachusetts,

Stephan J. Stranick
National Institute of Standards and Technology
(NIST), Gaithersburg, Maryland, U.S.A.

Chad Mirkin
Department of Chemistry, Northwestern University,
Evanston, Illinois, U.S.A.

Arthur ten Wolde
Confederation of Netherlands Industry and
Employers VNO-NCW, The Hague, The Netherlands

Shuming Nie
Department of Chemistry, Indiana University,
Bloomington, Indiana, U.S.A.

Frederick Tepper
Argonide Corp., Sanford, Florida, U.S.A.

Jens K. Norskov
Department of Physics, Technical University of
Denmark, Lyngby, Denmark
Mark Reed
Department of Electrical Engineering and Applied
Physics, Yale University, New Haven, Connecticut,

Gary Tompa
Structured Materials Industries, Inc., Piscataway,
New Jersey, U.S.A.
Robert Trew
Bradley Department of Electrical and Computer
Engineering, Virginia Technical Institute,
Blacksburg, Virginia, U.S.A.

David C. Rees
Astex Technology Ltd., Cambridge, U.K.

Etienne F. Vansant
Department of Chemistry, University of Antwerp
(UIA), Wilrijk, Belgium

Stacey L. Ristinmaa-Sörensen
Department of Physics, University of Lund,
Lund, Sweden

Younan Xia
Department of Chemistry, University of Washington,
Seattle, Washington, U.S.A.

John A. Rogers
Bell Laboratories, Lucent Technologies,
Murray Hill, New Jersey, U.S.A.

Peidong Yang
Department of Chemistry, University of California,
Berkeley, California, U.S.A.

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.


Nanoscience encompasses all scientific phenomena that transpire in dimensions spanning the
range of multiple atom clusters, molecular aggregates, supermolecular structures, polymers and
biomolecules. In other words, nanoscience is the science of the nanoscale—or the very, very
minute. Nanotechnology, the technological use of these properties and phenomena, has the
potential to revolutionize a breathtaking range of fields, across practically all domains of human
activity. The intense interest in using nanostructures stems from the promise that they boast
superior electrical, optical, mechanical, chemical, or biochemical properties. There is little
doubt that the use of these new materials and systems will lay the ground for the new
technological revolution of the 21st century. Research in nanoscience is exploding as scientists
from chemistry, physics, and biology, including colloid and polymer chemistry, materials and
surface science, and biochemistry, biophysics and molecular biology have begun to examine
the superior properties that characterize materials and phenomena at the nanoscale.
The Dekker Encyclopedia of Nanoscience and Nanotechnology is a vehicle by which
scientists and the interested public can explore the most recent developments in today’s
nanomaterials, and preview several of their foreseen applications of tomorrow. The subject
areas of this five-volume collective work include, but are not limited to, chemistry, physics,
molecular and quantum biology, materials science and engineering, and computer science. The
topics include fullerenes and carbon nanotubes, quantum dots and inorganic nanowires,
interfacial chemistry, nanostructures, analytical and characterization methods, design and
fabrication techniques of nanocomposites, properties of functional nanomaterials, nanostructured catalysts, molecular electronics, optical devices, bionanotechnology, colloidal phenomena—even future and environmental considerations about nanotechnology. In short, the
reference strives to encompass, document, and organize the enormous proliferation of
information that has emerged from the revolution at the nanoscale.
It is the editors’ hopes that the Dekker Encyclopedia of Nanoscience and Nanotechnology
will help researchers, graduate students, undergraduate students, and nonprofessionals all better
understand and participate in this remarkable emerging field. To keep the reference accessible,
the Encyclopedia is published in both online and print formats. The print version consists of
multiple traditional hardbound volumes with articles arranged alphabetically. The front matter
to each volume provides an alphabetical Table of Contents and a Topical Table of Contents. An
index at the back of each volume is intended as a further guide.
The online version of the Encyclopedia has been created by coupling the content of the print
edition with a powerful search engine and user-friendly interface. The online database is
dynamic, with additional articles added each quarter. As with the print edition, users will be
able to browse the alphabetical and topical Table of Contents, but they will also be able to
search for entries by keywords.
The editors of the Dekker Encyclopedia of Nanoscience and Nanotechnology could not have
accomplished their feat without the help of many. We first thank the authors of more than 300
articles which, as recognized experts in their fields, lend their credibility and prestige to the
Encyclopedia. In addition, the editors were joined by an esteemed International Editorial
Advisory Board whose input was crucial to shaping the reference. Success in the coordination
of the activities that has resulted in this final product is due to the remarkable staff at Marcel

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Dekker, Inc. We are indebted to the direction provided to us by Ellen Lichtenstein, Carolyn
Hall, Oona Schmid, Susan Lee, Joanne Jay, and Jeeran Ok. In particular, the creative ideas and
boundless energy that Oona Schmid has demonstrated is greatly acknowledged by the three of
us. We also thank Anita Lekhwani for her confidence in us as editors and Russell Dekker for his
support and encouragement.
James A. Schwarz
Syracuse University, Syracuse, New York
Cristian I. Contescu
Material Methods LLC, Newport Beach, California
Karol Putyera
Shiva Technologies, Syracuse, New York

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

A Note on Terminology

New terms, based on the prefix nano, have gained broad circulation, unified the older
terminology, and defined the topics of newly found disciplines. Just as the research community
has struggled to restrict when and where the prefix nano can be appropriately used, we too
struggled with the Dekker Encyclopedia of Nanoscience and Nanotechnology to avoid
puncturing every sentence with the prefix nano. As this terminology develops, the online
edition of the Encyclopedia will be able to incorporate these new conventions.
But at the time of publication of the first edition of the Encyclopedia these questions are still
unresolved. One definition that has been proposed in order to remove the ambiguity would limit
the use of the nano prefix to research and development of objects having the key property that
they have at least one dimension in the range of 1 to 100 nanometers. New advances in
synthetic methods for making such structures, combined with new analytical and manipulation
tools, made it possible to refine methods to the point where de novo designed objects with
nanoscopic dimension can, in many cases, be assembled in molecule-pure form or spatially
organized structures. These systems, designed through processes that exhibit fundamental
control over the physical and chemical attributes of molecular-scale structures, can be
combined to form larger structures.
However, the Dekker Encyclopedia of Nanoscience and Nanotechnology has numerous
entries that include the words micro and meso. Thus the use of the term nano, which, according
to one broadly circulated definition, only limits research and technology to development in the
length scale of approximately 1–100 nanometer range, is not simply a metric of length. Science
at the nanoscale does not accept rigid limits on dimensionality. Indeed the very utility of
nanoscience may be compromised by arbitrarily circumscribing its reach. After all, for ancient
Greeks, the term "nanos" meant a dwarf. Keeping this in mind, we attempted in this reference to
use the term nano to refer to objects and their subsequent processing into newly created
structures, devices, or systems that have novel properties and functions because of their small
and/or intermediate size. In other words, size and performance are the critical parameters that
provide the requisite conditions to justify the use of the term nano.
By adopting a more elastic definition, which on one hand spans sizes from a few
nanometer(s) to one (or a few) hundred(s) nanometers, but at the same time recognizes that the
properties and performance of nanoobjects are rooted in their nanoscopic size, we believe that
we made justice to all views that currently shape this field of continuous development and
hope that other investigators—at universities, state laboratories, and in industries—will follow
our lead.

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

A Note on Terminology
Volume 1

Adhesion Between Surfaces Coated with Self-Assembled Monolayers: Effect of Humidity /
Joan E. Curry, Sungsoo Kim

Adhesion of a Cell on a Substrate / Frédéric Pincet
Adsorption of Polymers and Proteins on Heterogeneous Surfaces / Vinay K. Gupta, Yu-Wen Huang
Aerosol Nanoparticles: Theory of Coagulation / Ken Won Lee, Soon-Bark Kwon
Aerospace Applications for Epoxy Layered-Silicate Nanocomposites / Chenggang Chen, Tia Benson Tolle
Anion Templated Self-Assembly: Inorganic Compounds / Louise S. Evans, Philip A. Gale
Anion-Templated Self-Assembly: Organic Compounds / Paul D. Beer, Mark R. Sambrook
Anodization Patterned on Aluminum Surfaces / Juchao Yan,
G. V. Rama Rao, Plamen B. Atanassov, Gabriel P. López
Antibodies and Other Ligand–Receptor Systems with Infinite Binding Affinity / Claude F. Meares
Atmospheric Nanoparticles: Formation and Physicochemical Properties / James N. Smith
Atomic Force Microscope Nanolithography on Organized Molecular Films / Seunghyun Lee, Haiwon Lee
Atomic Force Microscopy Simulation of Interaction Forces in CMP Applications / Ivan U. Vakarelski,
Scott C. Brown, Bahar Basim, Brij M. Moudgil
Atomic Force Microscopy and Single-Molecule Force Microscopy
Studies of Biopolymers / Nehal I. Abu-Lail, Terri A. Camesano
Atomic Force Microscopy Imaging and Force Spectroscopy of Microbial Cell Surfaces / Yves F. Dufreˆne
Atomic Force Microscopy Imaging Artifacts / Stephanie Butler Velegol
Atomic Force Microscopy Studies of Hydrogen-Bonded Nanostuctures on Surfaces
/ Holger Schönherr, Mercedes Crego-Calama, G. Julius Vancso, David N. Reinhoudt
Atomic Force Microscopy Studies of Metal Ion Sorption / Viriya Vithayaveroj, Sotira Yiacoumi, Costas Tsouris
Atomic Scale Studies of Heterogeneous Catalysts / Robert F. Klie,
Kai Sun, Mark M. Disko, Jingyue Liu, Nigel D. Browning
Axle Molecules Threaded Through Macrocycles / Daryle H. Busch, Thomas Clifford
Barcoded Nanowires / Rebecca L. Stoermer, Christine D. Keating
Barrier Properties of Ordered Multilayer Polymer Nanocomposites / Bon-Cheol
Ku, Alexandre Blumstein, Jayant Kumar, Lynne A. Samuelson, Dong Wook Kim
Basic Nanostructured Catalysts / Robert J. Davis
Biocatalytic Single Enzyme Nanoparticles / Jay W. Grate, Jungbae Kim
Biological and Chemical Weapon Decontamination by Nanoparticles / Peter K. Stoimenov, Kenneth J. Klabunde
Biological Path of Nanoparticle Synthesis / Kenji Iwahori, Ichiro Yamashita
Biomedical Applications: Tissue Engineering, Therapeutic Devices,
and Diagnostic Systems / J. Zachary Hilt, Mark E. Byrne
Biomedical Implants from Nanostructured Materials / Jeremiah Ejiofor, Thomas J. Webster
Bio-Microarrays Based on Functional Nanoparticles / Günter E. M. Tovar, Achim Weber
Bimetallic Layered Nanocomposites: Synthesis, Structure, and Mechanical Properties / Amit Misra,
Richard G. Hoagland
Biomimetic Approaches to the Design of Functional, SelfAssembling Systems / Mila Boncheva, George M. Whitesides

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Biomimetic Macrocyclic Receptors for Carboxylate Anion Recognition
/ Rocco Ungaro, Alessandro Casnati, Francesco Sansone
Biomolecular Structure at Interfaces Measured by Infrared Spectroscopy / Curtis W. Meuse
Bionanoparticles / Krishnaswami S. Raja, Qian Wang
Bioremediation of Environmental Contaminants in Soil, Water,
and Air / Xiomara C. Kretschmer, Russell R. Chianelli
Biosensor Applications: Porous Silicon Microcavities / Benjamin
L. Miller, Philippe M. Fauchet, Scott R. Horner, Selena Chan
Biosensor Applications: Surface Engineering / Genady Zhavnerko, Kwon-Soo Ha
Biosensors Based on Carbon Nanotubes / Yuehe Lin, Wassana Yantasee,
Fang Lu, Joseph Wang, Mustafa Musameh, Yi Tu, Zhifeng Ren
Biosensors for Detection of Chemical Warfare Agents / Elias Greenbaum, Miguel Rodriguez, Charlene A. Sanders
Biosurfaces: Water Structure at Interfaces / Yan-Yeung Luk
Block Copolymers Nanoparticles / Sandrine Pensec, Daniel Portinha, Laurent Bouteiller, Christophe Chassenieux
Carbon Forms Structured by Energetic Species: Amorphous, Nanotubes, and Crystalline / Yeshayahu Lifshitz
Carbon Nanotransistors / Po-Wen Chiu, Siegmar Roth
Carbon Nanotube Electrodes / Valentina Lazarescu
Carbon Nanotube Interconnects / Alain E. Kaloyeros, Kathleen A. Dunn, Autumn T. Carlsen, Anna W. Topol
Carbon Nanotube-Conducting Polymer Composites in Supercapacitors / Mark Hughes
Carbon Nanotubes and Metal Oxide Nanoribbons: Molecular Modeling / Amitesh Maiti
Carbon Nanotubes and Other Carbon Materials / Morinobu Endo, Yoong
Ahm Kim, Takuya Hayashi, Mauricio Terrones, Mildred S. Dresselhaus
Carbon Nanotubes: Chemistry / Bin Zhao, Hui Hu, Elena Bekyarova,
Mikhail E. Itkis, Sandip Niyogi, Robert C. Haddon
Carbon Nanotubes: Electrochemical Modification / Kannan Balasubramanian, Marko Burghard, Klaus Kern
Carbon Nanotubes: Electro-osmotic Flow Control in Membranes / Scott A. Miller, Charles R. Martin
Carbon Nanotubes: Energetics of Hydrogen Chemisorption / Ronald C. Brown
Carbon Nanotubes for Storage of Energy: Super Capacitors / Elzbieta Frackowiak
Carbon Nanotubes, Gas Adsorption on / Juan M. D. Tascón, Eduardo J. Bottani
Carbon Nanotubes: Hydrogen Storage and Its Mechanisms / Masashi
Shiraishi, Taishi Takenobu, Hiromichi Kataura, Masafumi Ata
Carbon Nanotubes: Incorporation Within Multilayered Polyelectrolyte Films / Jason H. Rouse, Peter T. Lillehei
Carbon Nanotube: Metal Matrix Composites / Efrain Carreno-Morelli
Carbon Nanotubes and Nanofibers as Novel Metal Catalyst Supports / Mark A. Keane
Carbon Nanotubes: Optical Properties / R. Saito, M. S. Dresselhaus,
G. Dresselhaus, A. Jorio, A. G. Souza Filho, M. A. Pimenta
Carbon Nanotubes: Supramolecular Mechanics / Boris I. Yakobson, Luise S. Couchman
Carbon Nanotubes: Thermal Properties / J. Hone
Catalysis by Supported Gold Nanoclusters / D. Wayne Goodman
Catalytic Processes over Supported Nanoparticles: Simulations / Vladimir I. Elokhin, Aleksandr V. Myshlyavtsev
Catalytic Properties of Micro-and Mesoporous Nanomaterials / Johannes A. Lercher, Andreas Jentys
Chaotic Transport in Antidot Lattices / Tsuneya Ando
Charge Carrier Dynamics of Nanoparticles / Fanxin Wu, Jin Z. Zhang
Charge Transfer in Metal–Molecule Heterostructures / Debasish Kuila, David B. Janes, Clifford P. Kubiak
Charge Transport Properties of Multilayer Nanostructures / Daniel M. Schaadt
Colloid Systems: Micelles, Nanocrystals, and Nanocrystal Superlattices / B. L. V. Prasad, Savka I. Stoeva
Colloidal Germanium Nanoparticles / Boyd R. Taylor, Louisa J. Hope-Weeks

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Colloidal Micro-and Nanostructures Assembled on Patterned Surfaces /
Aránzazu del Campo, Anne-Sophie Duwez, Charles-André Fustin, Ulrich Jonas
Colloidal Nanometals as Fuel Cell Catalyst Precursors / Helmut Bönnemann, K. S. Nagabhushana
Colloidal Nanoparticles: Aggregation Patterns at Model Molecular Surfaces / Hamidou Haidara, Karine Mougin
Colloidal Nanoparticles: Electrokinetic Characterization / Kunio Furusawa, Hideo Matsumura
Computational Analysis of Cadmium Sulfide (Cd S) Nanocrystals /
Stacie Nunes, Zhigang Zhou, Jeffrey D. Evanseck, Jeffry D. Madura
Computational Analysis of Switchable Catenanes / Xiange Zheng, Karl Sohlberg
Computational Analysis of Switchable Rotaxanes / Xiange Zheng, Karl Sohlberg
Computational Analysis Using Normal and Multibody Modes / Bryan C.
Hathorn, Donald W. Noid, Bobby G. Sumpter, Chao Yang, William A. Goddard
Computer-Aided Design of D N A-Based Nanoinstruments / Alexander Hillisch, Stephan Diekmann
Conducting Polymer Nanotubes: Electrochemical Synthesis and Applications / Seung Il Cho, Sang Bok Lee
Coordination Framework Topology: Influence of Using Multimodal Ligands / Neil R. Champness, Neil S. Oxtoby
Core/ Shell Hydrogel Nanoparticles / Clinton D. Jones, L. Andrew Lyon
Core/ Shell Nanospheres, Hollow Capsules, and Bottles / Gang Zhang, Kai Zhang, Yi Yu, Bai Yang
Cubosomes: Bicontinuous Liquid Crystalline Nanoparticles / Patrick T. Spicer
Volume 2
Dealloying of Binary Alloys: Evolution of Nanoporosity / Jonah Erlebacher
Dendritic Nanocatalysts / Kiyotomi Kaneda, Masahiko Ooe, Makoto Murata, Tomoo Mizugaki, Kohki Ebitani
Dimensionally Graded Semiconductor Nanoparticle Films / Arif
A. Mamedov, Nicholas A. Kotov, Nataliya N. Mamedova
Dip Pen Nanolithography(tm): Applications and Functional Extensions / Björn T. Rosner, Linette M. Demers
Dip-Pen Nanolithography Using M H A and Optical Inks / Brandon L. Weeks,
Aleksandr Noy, Abigail E. Miller, Jennifer E. Klare, Bruce W. Woods, James J. De Yoreo
Direct Force Measurement of Liposomes by Atomic Force
Microscopy / Guangzhao Mao, Xuemei Liang, K. Y. Simon Ng
Dissymmetrical Nanoparticles / Stéphane Reculusa, Christophe Mingotaud, Etienne Duguet, Serge Ravaine
D N A-Conjugated Metal Nanoparticles: Applications in Chip-Detection / Wolfgang Fritzsche
Deoxyribonucleic Acid (D N A) Hybridization: Electronic Control / Kimberly Hamad-Schifferli
D N A Interactions with Functionalized Emulsions / Thierry Delair
Dynamic Atomic Force Microscopy Studies to Characterize
Heterogeneous Surfaces / Ijeoma M. Nnebe, James W. Schneider
Electrical Double Layer Formation / Kun-Lin Yang, Sotira Yiacoumi, Costas Tsouris
Electrically Conducting Polymeric Nanostructures: Techniques for OneDimensional Synthesis / Andrew D. W. Carswell, Brian P. Grady
Electrically Functional Nanostructures / Orlin D. Velev, Simon O. Lumsdon
Electrochemical Langmuir Trough / Natalia Varaksa, Thomas F. Magnera, Josef Michl
Electrochemical Sensors Based on Functionalized Nanoporous
Silica / Yuehe Lin, Wassana Yantasee, Glen E. Fryxell
Electrochemical Toxicity Sensors / James F. Rusling
Electrochemically Self-Assembled Nanoarrays / S. Bandyopadhyay
Electron Microscopy Imaging Techniques in Environmental and Geological
Science / Satoshi Utsunomiya, Christopher S. Palenik, Rodney C. Ewing
Electronic Switches / Richard J. Nichols, David J. Schiffrin, Wolfgang Haiss
Enantioselectivity on Surfaces with Chiral Nanostructures / David M. Rampulla, Andrew J. Gellman
Environmental and Sensing Applications of Molecular Self-Assembly / G. E. Fryxell, R. Shane
Addleman, S. V. Mattigod, Y. Lin, T. S. Zemanian, H. Wu, Jerome C. Birnbaum, J. Liu, X. Feng

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Environmental Catalysts Based on Nanocrystalline Zeolites / Vicki H. Grassian, Sarah C. Larsen
Environmental Nanoparticles / Alexandra Navrotsky
Environmental Separation and Reactions: Zeolite Membranes /
Wei Xing, João C. Dinizda Costa, G. Q. (Max) Lu, Z. F. Yan
Ethane Preferred Conformation / Lionel Goodman, Vojislava Pophristic
Fluorescence-Voltage Single Molecule Spectroscopy of Conjugated Polymers / Young Jong Lee, Andre
J. Gesquiere, So-Jung Park, Paul F. Barbara
Fluorofullerenes / Olga V. Boltalina, Steven H. Strauss
Fractal Analysis of Binding Kinetics on Biosensor Surfaces / Harshala Butala, Ajit Sadana
Fullerenes and Carbon Nanotubes / Laszlo Mihaly
Fullerenes: Chemistry / Mark S. Meier
Fullerenes: Identification of Isomers Based on Nuclear Magnetic Resonance Spectra / Guangyu Sun
Fullerenes: Topology and Structure / G. Benedek, M. Bernasconi
Functionalization of Nanotube Surfaces / Stanislaus S. Wong, Sarbajit Banerjee
Functionalization of Silica Surfaces / V. A. Tertykh
Functionalization of Surface Layers on Ceramics / Toshihiro Ishikawa
Gold Nanoclusters: Structural Disorder and Chirality at the Nanoscale / Ignacio L. Garzón
Gold Nanoparticles on Titania: Activation and Behavior / Jose A. Rodriguez
Guests Within Large Synthetic Hydrophobic Pockets Synthesized
Using Polymer and Conventional Techniques / Bruce C. Gibb
Guests Within Large Synthetic Hydrophobic Pockets Synthesized via Self-Assembly / Bruce C. Gibb
Heterogeneous Surfaces with Nanosized Channel Lattices / Lifeng Chi, Michael Gleiche, Steven Lenhert, Nan Lu
Hierarchically Imprinted Nanostructures for Separation of
Metal Ions / Sheng Dai, Zongtao Zhang, Chengdu Liang
High-Resolution Mass Spectrometry Studies of Heterogeneous
Catalytic Reactions / Steven M. Thornberg, Deborah E. Hunka
High Strength Alloys Containing Nanogranular Phases / Dmitri Valentinovich Louzguine, Akihisa Inoue
Hydrogel Nanoparticles Synthesized by Cross-Linked Polyvinylpyrrolidone
/ Susmita Mitra, Dhruba Jyoti Bharali, Amarnath Maitra
Ice Nanotubes Inside Carbon Nanotubes / Kenichiro Koga, Hideki Tanaka
In Situ Electron Microscopy Techniques / Charles W. Allen
Indium Arsenide (In As) Islands on Silicon / P. C. Sharma, Kang L. Wang
Inorganic Nanotubes: Structure, Synthesis, and Properties / Reshef Tenne
Inorganic Nanotubes Synthesized by Chemical Transport Reactions / Maja Remskar
Integrated Methods: Applications in Quantum Chemistry / Stephan Irle, Keiji Morokuma
Intercalated Polypropylene Nanocomposites / Michael J. Solomon, Anongnat Somwangthanaroj
Interfacial Forces Between a Solid Colloidal Particle and a Liquid / Sarah A. Nespolo, Geoffrey W. Stevens
Interfacial Phenomena and Chemical Selectivity / Vinay K. Gupta
Ionic Strength Effects: Tunable Nanocrystal Distribution in Colloidal Gold Films
/ E. Stefan Kooij, E. A. Martijn Brouwer, Herbert Wormeester, Bene Poelsema
Iron Oxide Nanoparticles / Mamoru Senna
Island Nucleation, Predictions of / Maria C. Bartelt(Deceased)
Island Surfaces: Fabrication on Self-Assembled Monolayers / Hongjie Liu, Charles Maldarelli, M. Lane
Gilchrist, Alexander Couzis
Lab-on-a-Chip Micro Reactors for Chemical Synthesis / Paul D.
I. Fletcher, Stephen J. Haswell, Paul Watts, Xunli Zhang
Laser-Based Deposition Technique: Patterning Nanoparticles into
Microstructures / Edward M. Nadgorny, Jaroslaw Drelich

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Layer-by-Layer Assembly of Gold Nanoclusters Modified with Self-Assembled
Monolayers / Kohei Uosaki, Wenbo Song, Masayuki Okamura, Toshihiro Kondo
Layer-by-Layer Assembly of Polyelectrolyte Films: Membrane
and Catalyst Applications / Bernd Tieke, Ali Toutianoush
Layer-by-Layer Assembly of Semiconducting and Photoreactive Bolaform Amphiphiles
/ Jason Locklin, Derek Patton, Chuanjun Xia, Xiaowu Fan, Rigoberto C. Advincula
Layer-by-Layer Assembly of Thin Films of Mixed Nanoparticles / Jianchang Guo, Tianquan Lian, Encai Hao
Layer-by-Layer Electrostatic Self-Assembly / Michael J. McShane, Yuri M. Lvov
Layer-by-Layer Electroactive Thin Films to Layered Carbon Electrodes / Tarek R. Farhat
Liquid Crystals and Nanostructured Surfaces: A Novel System
for Detecting Protein Binding Events / Yan-Yeung Luk
Low-Dielectric Constant Materials for On-Chip Applications / Robert D. Miller
Luminescence of Nanoparticle-Labeled Antibodies and Antigens / Shaopeng Wang, Nicholas A. Kotov
Magnetic Behavior of Polymerized Fullerenes / Tatiana L. Makarova
Magnetic Nanomaterials: Conventional Synthesis and Properties / Dajie Zhang
Magnetic Nanomaterials: Nonconventional Synthesis and Chemical
Design / Luminita Patron, Ioana Mindru, Gabriela Marinescu
Magnetic Nanoparticles: Applications for Granular Recording Media / David E. Nikles, J. W. Harrell
Magnetic Nanoparticles: Preparation and Properties / Valérie Cabuil
Magnetic Nanoparticles in Fluid Suspension: Ferrofluid Applications
/ Carlos Rinaldi, Thomas Franklin, Markus Zahn, Tahir Cader
Magnetic Properties of Nanocomposite Permanent Magnets / Satoshi Hirosawa
Magnetic Properties of Nanoparticle Assemblies / Xiangcheng Sun
Mechanical Characterization of Nanoscale Biomaterials / Eunice Phay Shing Tan, Chwee Teck Lim
Mechanical Properties of Nanowires and Nanobelts / Zhong Lin Wang
Mechanosynthesis of Nanophase Powders / F. Miani, F. Maurigh
Volume 3
Mesoporous Materials (M41 S): From Discovery to Application
/ James C. Vartuli, Wielsaw J. Roth, Thomas F. Degnan, Jr.
Metal Clusters on Oxides / Ivan Stensgaard
Metal Nanoparticle Ensembles: Collective Optical Properties / Alexander Wei
Metal Nanoparticles and Their Self-Assembly into Electronic
Nanostructures / Venugopal Santhanam, Ronald P. Andres
Metal Nanoparticles Modified with Molecular Receptors / Jian Liu
Metal Nanoparticles Prepared in Supercritical Carbon Dioxide Solutions / Harry W. Rollins
Metal Nanoparticles Protected with Monolayers: Applications for Chemical Vapor Sensing and
Gas Chromatography / Jay W. Grate, David A. Nelson, Rhonda Skaggs, Robert E. Synovec, Gwen M. Gross
Metal Nanoparticles Protected with Monolayers: Synthetic Methods / Young-Seok Shon
Metal Nanoparticles Used as Catalysts / Naoki Toshima
Metal Nanostructures Synthesized by Photoexcitation / Kei Murakoshi, Yoshihiro Nakato
Metal Nanostructures Synthesized by Soft Chemical Methods and Shape Control / Yugang Sun, Younan Xia
Metal-Oxide Interfaces: Toward Design via Control of Defect Density / A. Bogicevic
Metal Oxide Nanoparticles / Ryan M. Richards
Metallic Nanopowders: An Overview / Frederick Tepper, Marat I. Lerner, David S. Ginley
Metallic Nanopowders: Rocket Propulsion Applications / Leonid Kaledin, Fred Tepper
Mica Surfaces: Charge Nucleation and Wear / James M. Helt, James D. Batteas
Microgel Dispersions: Colloidal Forces and Phase Behavior / Jianzhong Wu, Zhibing Hu
Microweighing in Supercritical Carbon Dioxide / You-Ting Wu, Christine S. Grant

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Mineral Nanoparticles: Electrokinetics / Mehmet S. Celik, Bahri Ersoy
Mixed Metal Oxide Nanoparticles / Pramesh N. Kapoor, Ajay
Kumar Bhagi, Ravichandra S. Mulukutla, Kenneth J. Klabunde
Molecular Assembly of Nanowires / Tomoyuki Akutagawa, Takayoshi Nakamura, Jan Becher
Molecular Assembly Organosilanes / Atsushi Takahara
Molecular Computing Machines / Yaakov Benenson, Ehud Shapiro
Molecular Designs for Self-Organized Superstructures / Makoto Tadokoro
Molecular Electronic Logic and Memory / Dustin K. James, James M. Tour
Molecular Electronics: Analysis and Design of Switchable and Programmable Devices
Using Ab Initio Methods / Pedro A. Derosa, Vandana R. Tarigopula, Jorge M. Seminario
Molecular Manipulator Dynamic Design Criteria / Andrés Jaramillo-Botero
Molecular Motor-Powered Nanodevices: Mechanisms for Control / Jacob J. Schmidt, Carlo D. Montemagno
Molecular Probes of Cation–Arene Interactions / George W. Gokel
Molecular Simulations of D N A Counterion Distributions / Alexander P. Lyubartsev
Molecular Switches / Jean-Pierre Launay, Christophe Coudret, Christian Joachim
Molecular Switches and Unidirectional Molecular Motors: LightInduced Switching and Motion / Richard A. van Delden, Ben L. Feringa
Molecular Wires / Dustin K. James, James M. Tour
Moore’s Law, Performance and Power Dissipation / Laszlo B. Kish
Motor Proteins in Synthetic Materials and Devices / Henry Hess, George Bachand, Viola Vogel
Multifunctional Ceramic Nanocomposites with Self-Diagnostic Ability of Catastrophic Damage /
Pavol Sajgalik, Zoltan Lences
Nano-Mesoscopic Interface: Hybrid Devices / Gianfranco Cerofolini
Nanoarrays Synthesized from Porous Alumina / Latika Menon
Nanoceramics / Abbas Khaleel
Nanocrystal Arrays: Self-Assembly and Physical Properties /
Xiao Min Lin, Raghuveer Parthasarathy, Heinrich M. Jaeger
Nanocrystal Dispersed Platinum Particles: Preparation and Catalytic Properties / Ioan Balint, Akane Miyazaki
Nanocrystalline Materials: Fatigue / Alexei Yu. Vinogradov, Sean R. Agnew
Nanocrystalline Materials: Synthesis and Properties / Alexandr I. Gusev
Nanocrystalline Oxides: Surfactants-Assisted Growth / Claudia L. Bianchi, Silvia Ardizzone, Giuseppe
Nanocrystallization / John H. Perepezko
Nanocrystals: Size-Dependent Properties and Emerging Applications / G. U. Kulkarni, P. John Thomas,
C. N.R. Rao
Nanocrystals: Synthesis and Mesoscalar Organization / C. N.R. Rao, P. John Thomas, G. U. Kulkarni
Nanocrystals Synthesized in Colloidal Self-Assemblies / M. P. Pileni
Nanodiamonds / Jean-Yves Raty, Giulia Galli
Nanoencapsulation of Bioactive Substances / Yury E. Shapiro
Nanoengineered Capsules with Specific Layer Structures / Lars Dähne, Claire S. Peyratout
Nanoengineered Polymer Microcapsules / Gleb B. Sukhorukov
Nanofilms in Giant Magnetoresistance Heads / Edward Grochowski, Robert E. Fontana, Jr.
Nanofiltration Separations / Eric M. V. Hoek, Anna Jawor
Nanolithography: Length-Scale Limitations / Takashi Ito
Nanomaterials and Molecular Devices: De Novo Design Theory / Kwang S. Kim, P. Tarakeshwar, Han Myoung Lee
Nanomaterials and Nanodevices Synthesized by Ion-Beam Technology / Dmitri Litvinov, Sakhrat Khizroev
Nanomaterials: Manufacturing, Processing, and Applications / Pramod
K. Sharma, Weifang Miao, Anit Giri, Srikanth Raghunathan

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Nanomaterials: New Trends / Richard Silberglitt
Nanomaterials: Recent Advances in Technology and Industry / Ganesh Skandan, Amit Singhal
Nanomechanical Resonant Devices: Surface Chemistry, Challenges, and Opportunities / Joshua A.
Henry, Debodhonyaa Sengupta, Melissa A. Hines
Nanoparticles: Generation, Surface Functionalization, and Ion Sensing / Jason J. Davis, Paul D. Beer
Nanoparticles: Synthesis in Polymer Substrates / Bai Yang, Junhu Zhang
Nanostructure and Dynamic Organization of Lipid Membranes / J. Gaudioso, D. Y. Sasaki
Nanostructure of Ionic Amphiphilic Block Copolymer Monolayer
at Air / Water Interface / Emiko Mouri, Hideki Matsuoka
Nanostructured Alloys: Cryomilling Synthesis and Behavior / David Witkin, Piers Newbery, Bing Q.
Han, Enrique J. Lavernia
Nanostructured Catalysts / Ravichandra S. Mulukutla
Nanostructured Catalytic Materials: Design and Synthesis / Hua Chun Zeng
Nanostructured Composites: Ti-Base Alloys / Jurgen Eckert, Jayanta Das, Ki Buem Kim
Nanostructured Composites Using Carbon-Derived Fibers / Peter M. A. Sherwood
Nanostructured Silica and Silica-Derived Materials / Ho-Cheol Kim, Geraud Dubois
Nanostructures Synthesized by Deposition of Metals on Microtubule Supports / Silke Behrens, Eberhard Unger
Nanostructured Materials Synthesized by Mechanical Attrition / Carl C. Koch
Nanostructured Materials Synthesized by Mechanical Means / H.-J. Fecht
Nanostructured Materials Synthesized in Supercritical Fluid / Yuehe Lin, Xiang-Rong Ye, Chien M. Wai
Nanostructured Multi-Layers for Applications in X-ray Optics / Michael Stoermer, Carsten
Michaelsen, Jörg Wiessman, Paulo Ricardo, Rüdiger Bormann
Nanostructured Ultrastrong Materials / Nicholas A. Kotov, Arif A. Mamedov, Dirk M. Guldi, Zhiyong
Tang, Maurizio Prato, James Wicksted, Andreas Hirsch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 
Nanostructures Based on Conducting Polymers / Shaun F. Filocamo, Mark W. Grinstaff
Nanostructures Based on Layered Transition Metal Chalcogenides / Russell R. Chianelli, Myriam Perez Dela Rosa
Nanostructures Derived from Phase Separated Polymers / Michael R. Bockstaller, Edwin L. Thomas
Nanostructures Replicated by Polymer Molding / Daniel B. Wolfe, J. Christopher Love, George M. Whitesides
Nanotechnology and Automotive Parts: Current Status and Future Prospects / Ganesh Skandan, Amit
Singhal, Damian Sobrevilla
Nanotube Sensors / Marc Wirtz, Charles R. Martin
Volume 4
Near-Field Microscopy Techniques / Björn T. Rosner, Daniel W. vander Weide
Near-Field Raman Spectroscopy / Eric Ayars
Near-Field Raman Spectroscopy: Enhancing Spatial Resolution
Using Metallic Tips / Satoshi Kawata, Yasushi Inouye
Near-Field Scanning Optical Microscopy: Chemical Imaging / Bogdan Dragnea
Noble Metals Nanoparticles on Carbon Fibers: Synthesis, Properties, and Applications / Dmitri A.
Bulushev, Igor Yuranov
Nucleation of Nanoparticles in Ultrathin Polymer Films / Pieter Stroeve
Nucleoside-and Nucleobase-Substituted Oligopyrrolic Macrocycles /
Vladimír Král, Martin Valík, Tatiana V. Shishkanova, Jonathan L. Sessler.
Oil-Filled Nanocapsules / Royale S. Underhill
Optical Molecular Devices / A. Prasannade Silva, Nathan D. Mc Clenaghan
Optical Nanosensors and Nanobiosensors / Brian M. Cullum
Ordered Vesicles at the Silicon–Water Interface / Duncan J. Mc Gillivray
Organofullerenes in Water / Eiichi Nakamura, Hiroyuki Isobe
Oxide Nanoparticles: Electrochemical Performance / Dominique Larcher, Jean-Marie Tarascon

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Palladium Nanoclusters: Preparation and Synthesis / Kiyotomi
Kaneda, Kwang-Min Choi, Tomoo Mizugaki, Kohki Ebitani
Phase Behavior of Nanoparticle Suspensions / S. Ramakrishnan, C. F. Zukoski
Phase Transfer of Monosaccharides Through Noncovalent Interactions / Elizabeth K. Auty, Anthony P. Davis
Photochemistry of Membrane-Coated Nanoparticles / Ulrich Siggel, Guangtao Li, Jürgen-Hinrich Fuhrhop
Photonic Crystal Fibers / P. St. J. Russell, J. C. Knight, T. A. Birks, P. J. Roberts
Photonic Applications of Printed and Molded Nanostructures / John A. Rogers
Photovoltaics for the Next Generation: Organic-Based Solar Cells / Sean E. Shaheen, David S. Ginley
Polyelectrolyte–Surfactant Complex Nanoparticles / Hans-Peter Hentze
Polyion Complex Micelles: Preparation and Physicochemical Properties / Atsushi Harada, Kazunori Kataoka
Polymer Colloids and Their Metallation / Lyudmila M. Bronstein
Polymer Nanocomposites with Particle and Carbon Nanotube Fillers / B. J. Ash, A. Eitan, L. S. Schadler
Polymer Nanofibers Prepared by Electrospinning / Roland Dersch, Andreas Greiner, Joachim H. Wendorff
Polymer Nanoparticles for Gene Delivery: Synthesis and Processing / Jie Wen, Kam W. Leong
Polymer Nanowires by Controlled Chain Polymerization / Yuji Okawa, Masakazu Aono
Polymer-Clay Nanocomposites and Polymer Brushes from Clay
Surfaces / Xiaowu Fan, Chuanjun Xia, Rigoberto C. Advincula
Polymeric and Biomolecular Nanostructures: Fabrication by Scanning Probe Lithography / Stefan Zauscher
Polymer-Mediated Self-Assembly of Nanoparticles / Tyler B.
Norsten, Amitav Sanyal, Roy Shenhar, Vincent M. Rotello
Polymer-Nanoparticle Composites / Kevin Sill, Seunghoo Yoo, Todd Emrick
Polypropylene and Thermoplastic Olefins Nanocomposites / Francis M. Mirabella, Jr.
Protein Adsorption Kinetics Under an Applied Electric Field / Paul R. Van Tassel
Protein Adsorption Studied by Atomic Force Microscopy / David T. Kim, Harvey W. Blanch, Clayton J. Radke
Protein Nanotubes as Building Blocks / Hiroshi Matsui
Proteins: Structure and Interaction Patterns to Solid Surfaces / Thomas J. Webster
Quantum Dot Arrays: Electromagnetic Properties / Sergey A. Maksimenko, Gregory Ya. Slepyan
Quantum Dot Lasers / Mikhail V. Maximov, Nikolai N. Ledentsov
Quantum Dots: Electronic Coupling and Structural Ordering / G. S. Solomon
Quantum Dots: Inelastic Light Scattering from Electronic Excitations / Christian Schüller
Quantum Dots Made of Cadmium Selenide (Cd Se): Formation
and Characterization / Kenzo Maehashi, Hisao Nakashima
Quantum Dots Made of Metals: Preparation and Characterization / J. P. Wilcoxon
Quantum Dots: Phonons in Self-Assembled Multiple Germanium
Structures / Jianlin Liu, Aleksandr Khitun, Kang L. Wang
Quantum Dots, Self-Assembled: Calculation of Electronic
Structures and Optical Properties / Andrew Williamson
Quantum Dots, Self-Formed: Structural and Optical Characterization / Shun-ichi Gonda, Hajime Asahi
Quantum Dots, Semiconductor: Atomic Ordering over Time / Peter Moeck
Quantum Dots, Semiconductor: Site-Controlled Self-Organization
/ S. Kohmoto, H. Nakamura, S. Nishikawa, T. Yang, K. Asakawa
Quantum Rods Made of Cadmium Selenide (Cd Se): Anistropy / Liang-shi Li, A. Paul Alivisatos
Raman Spectroscopy Studies of Carbon Nanotube–Polymer Composites / Bin Chen
Ring Structures from Nanoparticles and Other Nanoscale Building Blocks / Zhen Liu, Rastislav Levicky
Risk Assessment and Benefits / Douglas Mulhall
Volume 5
Scanning Near-Field Photolithography Techniques / Graham J. Leggett

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Scanning Single-Electron Transistor Microscopy / N. B. Zhitenev, T. A. Fulton
Scanning Tunneling Microscopy of Chiral Pair Self-Assembled Monolayers / Yuguang Cai, Steven L. Bernasek
Scanning Tunneling Microscopy Studies: Self-Assembly on Graphite / Thomas Müller
Self-Assembled Monolayers: Adsorption on and Desorption from Thiols / Pieter Stroeve
Self-Assembled Monolayers: Chemical and Physical Modification Under Vacuum Conditions
/ Jessica Torres, Anthony J. Wagner, Christopher C. Perry, Glenn M. Wolfe, D. Howard Fairbrother
Self-Assembled Monolayers: Effects of Surface Nanostructure on
Wetting / Jun Yang, Jingmin Han, Kelvin Isaacson, Daniel Y. Kwok
Self-Assembled Silane Monolayers: Conversion of Cyano to Carboxylic
Termination / Chandra Sekhar Palla, Alexander Couzis
Self-Assembled Structures / Anna Cristina Samia, Xiao-Min Lin
Self-Assembled Thin Films: Optical Characterization / Herbert Wormeester, E. Stefan Kooij, Bene Poelsema
Self-Assembly and Biocatalysis of Polymers and Polymer–Ceramic Composites / Christy
Ford, Vijay John, Gary Mc Pherson, Jibao He, Joseph Akkara, David Kaplan, Arijit Bose
Self-Assembly and Multiple Phases of Layered Double Hydroxides / Zhi Ping Xu, Paul S. Braterman
Self-Assembly Directed by N H–O Hydrogen Bonding / Katrina A. Jolliffe, Leonard F. Lindoy
Self-Assembly of Cavitand-Based Coordination Cages / Laura Pirondini, Enrico Dalcanale
Self-Assembly of Chiral and Pseudochiral Molecules at Interfaces / Dalia G. Yablon
Self-Assembly of Cyclic Peptides in Hydrogen-Bonded Nanotubes / Roberto J. Brea, Juan R. Granja
Self-Assembly of Nanocolloidal Gold Films / E. Stefan Kooij, E. A. Martijn
Brouwer, Agnes A. Mewe, Herbert Wormeester, Bene Poelsema
Self-Assemby of Organic Films for Nonlinear Optical Materials / Matthew Guzy, Richey
M. Davis, Patrick J. Neyman, Charles Brands, J. R. Heflin, Harry W. Gibson, Kevin E. Van Cott
Self-Assembly of Porphyrinic Materials on Surfaces / Charles Michael
Drain, James D. Batteas, Gabriela Smeureanu, Sandeep Patel
Self-Assembly of Redox-Responsive Receptors / Kay Severin
Self-Assembly of Two-and Three-Dimensional Nanostructures for
Electronic Applications / Ilona Kretzschmar, Mark A. Reed
Semiconductor Nanowires for Applications in Macroelectronics / Yugang Sun, John A. Rogers
Semiconductor Nanowires: Nanoscale Electronics and Optoelectronics / Yu Huang, Xiangfeng Duan,
Charles M. Lieber
Semiconductor Nanowires: Rational Synthesis / Xiangfeng Duan, Charles M. Lieber
Sensors Based on Chemicurrents / B. Roldan Cuenya, E. W. Mc Farland
Shock-Induced Synthesis of Nanocomposite Magnetic Materials / Naresh N. Thadhani, Z. Q. Jin
Silane Self-Assembled Monolayers: Nanoscale Domains by Sequential Adsorption / Nitin Kumar
Silica Nanotubes: Wetting and Diffusion Phenomena / Kenji Okamoto, Karthik Jayaraman, Sang Jun
Son, Sang Bok Lee, Douglas S. English
Silicon Nanoclusters: Simulations / Aaron Puzder
Silicon Nanocrystals: Quantum Confinement / James R. Chelikowsky
Single-Cell Level Mass Spectrometric Imaging / Sara G. Ostrowski, Andrew G. Ewing, Nicholas Winograd
Single Molecule Spectroscopy Studies to Characterize Nanomaterials / Daniel A. Higgins, Yanwen Hou
Single-Walled Carbon Nanotubes: Density Functional Theory Study on
Field Emission Properties / Xiaofeng Duan, Brahim Akdim, Ruth Pachter
Single-Walled Carbon Nanotubes: Geometries, Electronic Properties,
and Actuation / Guangyu Sun, Marc Nicklaus, Miklos Kertesz
Single-Walled Carbon Nanotubes: Separation Using Capillary Electrophoresis / Stephen K. Doorn
Single-Walled Carbon Nanotubes: Structures and Symmetries / Carter T. White, John W. Mintmire
Small Amplitude Atomic Force Microscopy / Peter M. Hoffmann
Smart Nanotubes for Biotechnology and Biocatalysis / Charles R. Martin, Punit Kohli

Copyright D 2004 by Marcel Dekker, Inc. (except as noted on the opening page of each article.) All Rights Reserved.

Spin-Coated Cyanogels / Shu Zhu, Andrew B. Bocarsly
Stability of Nanostructures on Surfaces / Karsten Pohl
Structural and Optical Anisotropy in Nanoporous Anodic Aluminum Oxide
/ E. Stefan Kooij, Aurelian C. Gâlcă, Herbert Wormeester, Bene Poelsema
Structural Base of Halide Transport Through Biological Membranes / Lars-Oliver Essen
Structural Color / Pete Vukusic
Structural Nanomaterials / Joanna R. Groza, Jeffrey C. Gibeling
Structural Transitions in Thin Films / Rajarshi Banerjee, Gregory B. Thompson, Hamish L. Fraser
Sum Frequency Generation Vibrational Spectroscopy Studies
of Molecular Orientation at Interfaces / Zhan Chen
Superconducting Nanowires Templated by Single Molecules / Alexey Bezryadin,
Anthony Bollinger, David Hopkins, Michael Murphey, Mikas Remeika, Andrey Rogachev
Supramolecular Aggregates with Controlled Size and Shape on Solid Surfaces
/ Takashi Yokoyama, Toshiya Kamikado, Shiyoshi Yokoyama, Shinro Mashiko
Supramolecular Networks Synthesized in Nanoparticle-Polymer Mixtures / Anna C. Balazs, Gavin A. Buxton
Surface Chemistry of Nanocrystalline Oxides of Magnesium and Aluminum / Richard M. Narske
Surface-Enhanced Raman Scattering (SERS) / Adam M. Schwartzberg, Jin Z. Zhang
Surface Forces on Nanoparticles Determined by Direct Measurement
/ Jeong-Min Cho, Georgios Pyrgiotakis, Wolfgang M. Sigmund
Surface Plasmon Spectra of Silver and Gold Nanoparticle Assemblies / Mondona Zangeneh, Roger Terrill
Template-Directed Assembly of Dinuclear Triple-Stranded Helicates / Markus Albrecht
Templating Aerogels for Tunable Nanoporosity / Aydin K. Sunol, Sermin G. Sunol
Templating Polymer Crystal Growth Using Block Copolymers / Yueh-Lin Loo
Thermal Conductivity of Nanoceramics / Paul G. Klemens
Thermal Effect on the Luminescence Properties of Quantum Dots / X. B. Zhang, R. D. Dupuis
Thermal Properties of Nanobridges / Jeong Won Kang, Ho Jung Hwang
Thermodynamics at the Meso-and Nanoscale / Mikhail A. Anisimov
Three-Dimensional Nanofabrication Using Multiphoton Absorption / John T. Fourkas, Tommaso Baldacchini
Titanium Dioxide Coatings on Stainless Steel / Ganesh
Balasubramanian, Dionysios D. Dionysiou, Makram T. Suidan
Toxicological Effects and Screening of Engineered Nanoparticles / Paul Borm, Ken Donaldson
Tribology at the Nanoscale / Peter T. Cummings, Clare Mc Cabe
Tribology of Inorganic Nanoparticles / Lev Rapoport
Tungsten Carbide-Cobalt Nanocomposites: Production and
Mechanical Properties / Purnesh Seegopaul, Zhigang Fang
Virus Nanoparticles: Adsorption and Organization on Substrates / Jiyu Fang
X-Ray Absorption Studies of Catalyst Nanostructures / J. T. Miller, M. K. Neylon, C. L. Marshall, A. J. Kropf
Yttria-Tetragonally Stabilized Zirconia: Aqueous Synthesis and Processing / R. Allen Kimel

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Updates available Soon

Aerosol Nanoparticles: Theory of Coagulation


Ken Won Lee
Soon-Bark Kwon
Kwangju Institute of Science and Technology, Gwangju, South Korea

Many important physical properties of natural or manmade aerosol particles such as light scattering, electrostatic charges, and toxicity, as well as their behavior
involving physical processes such as diffusion, condensation, and thermophoresis, depend strongly on their size
distribution. An important aerosol behavior mechanism
affecting the size distribution of aerosol particles is
coagulation. Aerosol particles suspended in a fluid may
come into contact because of their Brownian motion, or as
a result of their relative motion produced by external
forces (e.g., gravity, hydrodynamic forces, electrical
forces, etc.). The result is a continuous decrease in
number concentration and an increase in particle size. The
theory of coagulation was originally devised for particles
in liquids and was later extended to aerosols. In the case of
solid particles, the process is sometimes called agglomeration, and the resulting particle clusters are known as
agglomerates. Therefore in many basic and applied fields
(e.g., synthesis of nanostructured material via gas-phase
synthesis), the evolution of the particle size distribution
because of coagulation is of fundamental importance
and interest.
Aerosol coagulation is caused by relative motion
among particles. When the relative motion is because
of Brownian motion, the process is called Brownian
coagulation. Brownian coagulation is a spontaneous
and ever-present phenomenon for aerosols. When the
relative motion arises from external forces such as gravity or electrical forces, or from aerodynamic effects,
the process is called kinematic coagulation. Kinematic coagulation includes gravitational coagulation, turbulent coagulation, electrostatic coagulation, etc.
The objective of this chapter is to review the theories
of coagulation describing how particle number concentration and particle size change as a function of time.
To do that, first, an overview of some important coagulation mechanisms is presented. Next, various solution
techniques for the coagulation equation are comparatively reviewed.

Dekker Encyclopedia of Nanoscience and Nanotechnology
DOI: 10.1081/E-ENN 120009076
Copyright D 2004 by Marcel Dekker, Inc. All rights reserved.

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.

When an aerosol contains particles of the same size, it is
called monodisperse, whereas if particles are present in a
variety of sizes, the aerosol is polydisperse. Coagulation
of a monodisperse aerosol was developed for Brownian
coagulation by Smoluchowski.[1] Smoluchowski derived
the monodisperse coagulation equation by solving the
diffusion equation around a single particle, and by
obtaining the flux of other particles toward it. He
assumed that particles adhere at every collision and
that particle size changes slowly. The change in particle number concentration is represented by the following equation:
¼ 2Kco N 2


where N is the number concentration of the particles, t is
the time, Kco (= 2pdpD) is the Brownian coagulation
coefficient in the continuum regime, dp is the diameter
of the particles, and D is the diffusion coefficient of the
particles. The diffusion coefficient D is given by the
following Stokes–Einstein equation:
D ¼

kB T


where kB is the Boltzmann constant, T is the absolute
temperature, and m is the gas viscosity. Using Eq. 2, Kco
in Eq. 1 can be expressed as follows:
Kco ¼

2kB T


By integrating Eq. 1, the number concentration is determined as a function of time as follows:
1 þ 2Kco No t
where No is the initial value for N.


Fig. 1 Coagulation of monodisperse aerosol particles.

Because the rate of coagulation is proportional to N2, it
is rapid at high concentrations but decreases as coagulation reduces the concentration of particles. This relationship is shown in Fig. 1, which presents a plot of the
number concentration of a monodisperse aerosol as a
function of time. When the data are replotted as 1/N vs. t, a
straight line is obtained. The quantity 1/N is in units of
cubic centimeters and represents the average gas volume
per particle. The slope of the line is the coagulation
coefficient Kco.

In ‘‘Coagulation of Monodisperse Aerosols,’’ the equations describing coagulation were introduced for a
monodisperse aerosol. We now consider the more complicated situation of polydisperse aerosols where a range
of particle sizes is present. Because the rate of coagulation depends on the range of sizes present, the mathematics become much more complicated and no explicit
solution exists.
The change in the particle size distribution of a polydisperse aerosol by coagulation is represented by the following population balance equation:[2]
@nðv; tÞ



bðv  v; vÞnðv  v; tÞnðv; tÞ
Z 1
 dv  nðv; tÞ
bðv; vÞnðv; tÞdv


Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.


where n(v,t) is the particle size distribution function at
time t, and b(v,v) is the collision kernel for two particles
of volume v and v. The first term in the right-hand side of
Eq. 5 represents the increase in particles with volumes
between v and (v +dv) from the combination of particles of
volume v v and v. The second term in the right-hand side
of this equation represents the loss of particles with
volumes between v and (v+ dv) resulting from the coagulation of particles of volume v and v. Thus this equation gives an expression for the net rate of change of
particles whose volumes lie between v and (v +dv). The
collision kernel b(v,v) is dependent on the collision
mechanism as well as on the particle size of two colliding particles.

Brownian Coagulation
The Brownian collision kernel can be derived by either
the kinetic theory of gases, or by the continuum
diffusion theory according to particle size. Particles
much smaller than the mean free path length of the
gas molecules behave like molecules, and the kinetic
theory of gases must be used to derive the collision
kernel. In the meanwhile, for the particles much larger
than the mean free path of the gas molecules, the
continuum diffusion theory should be used. Generally,
the Knudsen number Kn (=l/r), with l as the mean
free path length of the surrounding gas molecules and

r as the particle radius, is used to define the particle
size regime.
In the free molecule regime, where the Knudsen
number is larger than about 50, bfm(v,v) results from the
kinetic theory of gases and is given as:[3]

Table 1 Coefficients for enhancement function f (KnD)

1 1
1=3 2
bfm ðv; vÞ ¼ Kfm ðv þ v Þ
v v

Fuchs and Sutugin[7]

where Kfm = (3/4p)1/6(6kBT/r)1/2 is the Brownian coagulation coefficient for the free molecule regime and r is the
particle density.
In the continuum regime, where the Knudsen number is
smaller than about 1, bco(v,v) is derived by the continuum
diffusion theory as follows:

CðvÞ CðvÞ
bco ðv; vÞ ¼ Kco ðv1=3 þ v1=3 Þ 1=3 þ 1=3


where C = 1 +Kn{1.142 +0.558 exp( 0.999/Kn)} is the
gas slip correction factor.[4]
The entire transition regime is characterized by
Knudsen numbers in the range of  1 < Kn < 50. In the
transition regime, the coagulation rate is described neither
by the continuum diffusion theory nor by the simple
kinetic theory. Fuchs[5] found a semiempirical solution of
the collision kernel by assuming that outside of a certain
distance, namely, an average mean free path of an aerosol
particle, the transport of particles is described by the
continuum diffusion theory including the slip correction,
and that inside the distance, the particles behave like in a
vacuum and the transport is described by the kinetic
theory. The two theories were brought together by
matching the fluxes at the absorbing sphere radius.
This so-called flux matching was the basis for most of
the following theories because of its phenomenological
approach and the guarantee that the collision kernel is
valid over the entire size regime. All theories dealing with
an absorbing sphere use a correction function first
calculated by Fuchs. This function is mainly expressed
as an enhancement of the collision kernel for the
continuum regime including the slip correction:
bB ðv; vÞ ¼ Kco ðv1=3 þ v1=3 Þ

CðvÞ CðvÞ
f ðKnD Þ


bco ðv;vÞ
where KnD ¼ 2b
vÞ and the subscripts ‘‘co’’ and ‘‘fm’’
fm ðv;
designate the continuum regime including the slip
correction and the free molecule regime, respectively.
Dahneke[6] described the diffusion process as a mean free
path phenomenon. To obtain the coagulation coefficient,
Dahneke also matched the two fluxes but at a distance
which is the mean free path of the particles. To compare

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.



Harmonic mean

3 D12
2 _ lp







the different theories, the following general enhancement
function f(KnD) is used:
f ðKnD Þ ¼

1 þ B1 KnD
1 þ B2 KnD þ B3 Kn2D


The coefficients B1, B2, and B3 are given for some theories
in Table 1. By comparing various theories on the collision
kernel in the transition regime, Otto et al.[8] recommended
Dahneke’s theory to be used partially for its simplicity and
partially for its accuracy.
Gravitational Coagulation
Kinematic coagulation is coagulation that occurs as a
result of relative particle motion caused by mechanisms
other than Brownian motion. From this section through
‘‘Electrostatic Coagulation,’’ various kinematic coagulations are introduced.
Particles of different sizes will settle at different rates
under the influence of gravity and thereby create relative
motion between them, which leads to collision and
coagulation. This mechanism is called gravitational
coagulation. The collision kernel by gravitational coagulation is expressed as the following equation when the slip
correction factor is neglected:[9]
bG ðv; vÞ ¼ KG eðr; r Þðr þ r Þ2 jr 2  r 2 j
where KG ¼ 9m is the gravitational coagulation constant, g is the gravity constant,
h  r is ithe particle
h  density,
3v 1=3
3v 1=3
is the gas viscosity, and r ¼ 4p
and r ¼ 4p
the radii of the colliding particles. e(r,r) is the collision
efficiency, which can be expressed as follows:
eðr; r Þ ¼
if r

2ðr þ r Þ2

r ; yc ¼ r and if r > r ; yc ¼ r


When both the Brownian and gravitational coagulations
are significant, the two collision kernels bB and bG are
commonly added to predict the behavior of aerosols. This
simple addition would appear to be based on a physical


Fig. 2 Comparison of Brownian and gravitational coagulation kernels. (From Ref. [11].)

picture of each of the mechanisms acting independently
with neither affecting the other, but it would seem that this
is not the case. Thus the combined kernel was suggested
by Simon et al.,[10] and their kernel is plotted in Fig. 2
with the sum kernel and each kernel of the Brownian and
gravitational coagulations. Their kernel describing the
combined effect of Brownian and gravitational coagulations increases the rate of coagulation compared with the
sum kernel in the size range of 0.1–1 mm. On the contrary,
Qiao et al.[12] reported that weak Brownian diffusion, the
effect of which is nonlinearly coupled with gravity, can
act to decrease the coagulation rate.

different velocities and this will also lead to collisions.
This mechanism is called ‘‘accelerative mechanism.’’
Saffman and Turner[13] derived the following collision
kernel by combining the shear mechanism and the accelerative mechanism:

bT ðv1 ; v2 Þ ¼


Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.



ðr1 þ r2 Þ2 ðw2a þ w2s Þ1=2



ðr1 þ r2 Þ 3 1  f




Dvf 2 1
2 e

þ ðr1 þ r2 Þ

Turbulent Coagulation
In many physical situations, the flow field in a fluid is
turbulent. There are two ways in which turbulence causes
collisions between neighboring particles. First, there are
spatial variations of the turbulent motion. Because of this
process, collision mechanism is conventionally called
‘‘shear mechanism.’’ Second, each particle moves relative to the air surrounding it, owing to the fact that the
inertia of a particle is different from that of an equal
volume of air. Because the inertia of a particle depends on
its size, neighboring particles of unequal size will have


ðt1  t2 Þ2


where ri [=(3vi/4p)1/3] is the particle radius, rf is the fluid
density, rp is the particle density, e is the turbulent energy
dissipation rate, and n is the kinematic viscosity of the
fluid. The particle relaxation time ti including the
Cunningham slip correction factor Cc,i is defined as:
ti ¼

Cc;i ð2rp þ rf Þri2


where m is the dynamic viscosity of the fluid. The average acceleration of eddies in the dissipation range

ðDvf =DtÞ2 is defined as:[14]



b ¼

¼ 1:16e3=2 n1=2


The first and second terms in the square root term on the
right-hand side of Eq. 12a represent the accelerative
mechanism and shear mechanism, respectively. However, under more vigorous turbulence or with larger
particles, the approaching particles may no longer be
entrained completely by the smallest eddies, so they will
have less correlated velocities.
Recently, Kruis and Kusters[15] analyzed this problem
using a turbulence spectrum, which describes both the
viscous subrange and the inertial subrange. In their work,
the relative particle velocity w is represented by the
following equations:
w2a ¼ 3ð1  bÞ2 v2f


ð1 þ y1 Þð1 þ y2 Þ ð1 þ gy1 Þð1 þ gy2 Þ



v21 y1
v22 y2
v1 v2
þ2 2
vf Cc;1 vf Cc;2

y1 y2
Cc;1 Cc;2

The root mean square (rms) fluid velocity vf is expressed



where g is the spectrum constant, which usually has a
value between 10 and 100. The turbulent energy k (k= 3/
2vf2) and the dissipation rate e are obtained mostly from
fluid dynamic simulations. The added mass coefficient b
is defined as:

v1 v2

The dimensionless particle relaxation time yi is defined as:
yi ¼



where TL is the Lagrangian time scale:
TL ¼



The rms particle velocity vi, valid in both the viscous and
the inertial subranges of turbulence, is represented as:

1 þ b2 yi
1 þ b2 gyi

g  1 1 þ yi
gð1 þ gyi Þ

Electrostatic Coagulation

ðy1 þ y2 Þ

w2s ¼ 0:238bv2f


whereas the velocity correlation is (see equation below):


1 þ y1 þ y2
ðy1 þ y2 Þ2  4y1 y2
ð1 þ y1 Þð1 þ y2 Þ


2rp þ rf


Charged particles may experience either enhanced or
retarded coagulation rates depending on their charges. For
a unipolar aerosol, it is necessary to consider electrostatic
dispersion (i.e., the tendency of charged particles of the
same sign to move away from each other). This dispersion
tends to reduce the concentration of an aerosol, for
example, by causing particles to deposit on the walls of
any containing vessel or nearby surface. In the presence of
particle charging, the collision kernel of particles must be
corrected by:
bE ðv1 ; v2 Þ ¼

bn ðv1 ; v2 Þ


where the subscript ‘‘n’’ designates neutral particles. The
Fuchs stability function W is given by:[16]
W ¼

expðkÞ  1

k ¼

z1 z2 e 2
ðr1 þ r2 ÞkB T


where z1 and z2 are the numbers of unit charges contained
in particles, and e is the electron charge. For k > 0 (like
charge), W >1 and coagulation is retarded from that for
neutral particles. Conversely, for k < 0 (unlike charge),
W <1 and coagulation is enhanced.

ðy1 þ y2 þ 2y1 y2 Þ þ bðy21 þ y22  2y1 y2 Þ þ b2 ðy21 y2 þ y1 y22 þ 2y1 y2 Þ
ðy1 þ y2 Þð1 þ y1 Þð1 þ y2 Þ

ðy1 þ y2 þ 2gy1 y2 Þ þ bgðy21 þ y22  2y1 y2 Þ þ b2 ðg2 y21 y2 þ g2 y1 y22 þ 2gy1 y2 Þ

gðy1 þ y2 Þð1 þ gy1 Þð1 þ gy2 Þ

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.



Methods of solving a coagulation equation were summarized by Williams and Loyalka.[17] These methods
range from the discrete (computationally intensive) and
sectional models in which Eq. 5 is transformed into a
number of differential equations, to the less accurate monodisperse models. Approximate solutions can be found
using the method of moments. Exact solutions for asymptotic limiting cases can be obtained with the self-preserving theory.
Sectional Method
Because solving the coagulation equation with a direct
numerical method is impractical owing to its timeconsuming property, several approximate methods have
been developed. The sectional method developed by
Gelbard et al.[18] is known as a very accurate but
comparatively time-efficient tool. Their model solved a
one-dimensional form of the aerosol general dynamic
equation by dividing the particle size domain into a finite
number of sections by particle volume, and by calculating
the addition and subtraction of particle mass to each
section. The model assumed that particles kept their
spherical shape during growth; therefore the volume
sections corresponded to sections of particle size. However, as irregular particles have become omnipresent in
nanoparticle production (e.g., generation of titanic or
silica particles by gas-phase reaction), substantial prog-

ress has been made in developing models that account
for irregular particle shape through fractal dimensions.
The volume and surface area of irregularly shaped
particles were chosen as the two particle size dimensions
because these are the most commonly employed powder
properties in engineering applications. Then the twodimensional aerosol dynamic equations were solved by
extending a one-dimensional sectional technique to the
two-dimensional space.[19] A two-dimensional particle
size distribution function is defined as nt(v,a), where
nt(v,a)dadv is the number density of particles having a
volume between v and v +dv and a surface area between
a and a+ da at time t. For an aerosol that is formed by
gas-phase reaction at high temperatures, the rate of
change in nt(v,a) is given by the rate of simultaneous
coagulation and coalescence (by sintering) among
aerosol particles:[19,20]
@nt ðv; aÞ

@nt ðv; aÞ

@nt ðv; aÞ


The coagulation term in Eq. 23 can be obtained by
extending the classical collision theory to the two-dimensional space v,a as:

@nt ðv; aÞ

Z v
v  v 2=3
y a>
a0 þ
2 0

Fig. 3 Self-preserving size distribution for Brownian coagulation.

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.

Z v a0
  2=3 bv;vv ð
a; a  
aÞnt ðv; 


adv  nt ðv; aÞ
 nt ðv  v; a  





v0 a0

  2=3 bv;v ða; 
aÞnt ðv; 



where v0 and a0 are the volume and surface area, respectively, of the primary particle, which is the smallest
possible particle (e.g., a molecule or a monomer).
The sintering contribution in Eq. 23 is related to the
particle sintering rate through the continuity:[20]

@nt ðv; aÞ
@ da
nt ðv; aÞ
@a dt
The sintering of solid particles or highly viscous fluids can
be the result of various sintering mechanisms such as
solid-state surface or volume diffusion and viscous flow.
For the mechanism of viscous flow coalescence beyond a
small initial time scale, Hiram and Nir[21] found that the
neck size approaches the radius of the resulting sphere
exponentially. For longer times, this leads to a similar
behavior for the particle surface:[20]
¼  ða  afinal Þ


where afinal is the surface area of the completely fused
sphere of volume v, and tf is the characteristic coalescence
time. The characteristic time for coalescence or sintering
tf is the time needed to reduce by 63% the excess agglomerate surface area over that of a spherical particle
with the same mass.
Therefore by combining Eqs. 23 and 24 and Eqs. 25
and 26, the overall aerosol population balance equation
can be written as:
@nt ðv; aÞ 1 @

tf @a





 2=3 #
a0 nt ðv; aÞ


v  v 2=3
y a>
a0 þ

Self-Preserving Solution
One of the interesting features of coagulation known to
date is that the shape of the size distribution of suspended
particles undergoing coagulation often does not change
after a long time and the distribution becomes selfpreserving.[22–24]
Conventionally, in the self-preserving formulation, the
dimensionless particle volume is defined as:
Z ¼



and the dimensionless size distribution density function is
defined as:
CðZÞ ¼

nðv; tÞfðtÞ
N 2 ðtÞ

þ ð2ab  bZ1=3  aZ1=3 ÞCðZÞ

Z  Z 1=3
CðZ  ZÞCðZÞ 1 þ
dZ ¼ 0

ð1 þ abÞZ




Z 1Z v a0
aÞnt ðv; aÞdadv
adv  nt ðv; aÞ
 2=3 bv;v ða; 




Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.


where a ¼ 0 Z1=3 CðZÞdZ and b ¼ 0 Z1=3 CðZÞdZ.
Friedlander and Wang derived analytical solutions of
Eq. 30, shown in Eqs. 31 and 32, for small Z regime and
for large Z regime, respectively:
expð1:758Z1=3  1:275Z1=3 Þ

CðZÞ ¼ 0:915 expð0:95ZÞ

  2=3 bv;vv ð
a; a  
aÞnt ðv; 
aÞnt ðv  v; a  aÞ


Friedlander and Wang[24] obtained the following equation
for the Brownian coagulation in the continuum regime:

CðZÞ ¼

v0 a0


Eq. 27 is a two-dimensional partial integrodifferential
equation that needs to be solved numerically. In solving
the conventional one-dimensional coagulation equation, a
sectional model has been developed. The sectional method
proves to be both computationally efficient and numerically robust, especially in dealing with aerosols having an
extremely large size spectrum. Xiong and Pratsinis[19]
presented a set of M ordinary differential equations
(ODEs) using an efficient ODEs solver.



Eq. 30 can be solved numerically for the entire Z range.
The results obtained by Friedlander and Wang are shown
in Fig. 3 together with the results of numerical simulations
by Vemury et al.,[25] who solved the coagulation equation
(Eq. 5) using the sectional method of Landgrebe and
Pratsinis.[26] Lai et al.[27] used the above technique to


derive the self-preserving size distribution for the free
molecule regime.
Wang and Friedlander[28] applied the same method to
the Brownian coagulation either with slip correction or
with simultaneous shear flow. However, in their work,
they had to introduce an unrealistic assumption that some
parameters are special functions of time. Pich et al.[29]
obtained the self-preserving particle size distribution for
the problem of simultaneous coagulation and condensation, but the similar constraint confined the application of
the solution obtained.
Moment Method
Although the self-preserving size distribution theory
played a very important role for researchers in understanding the coagulation mechanism, one shortcoming of
the theory is its inability to resolve the size distribution for
the time period before an aerosol attains the selfpreserving size distribution. Therefore it was still necessary to resort to numerical calculations. However, during
coagulation, the size distribution of particles changes by
the interaction of particles in so many size classes at each
time step that the computing time becomes excessive for
the calculation of the change of size distribution of
particles. To overcome this problem and to accelerate the
computations, much effort has been made. Cohen and
Vaughan[30] succeeded in reducing the coagulation equation to a set of ODEs for the moments of size distribution.
By choosing a specific functional form for the distribution
of the particle size, they were able to calculate the parameters of the size distribution as a function of the three
leading moments. This method, known as the moment
method, has the advantage of simplicity while providing
important information on the change of the size distribution of aerosol.[31] Therefore the moment method has been
widely applied in the simulation of aerosol coagulation.[32,33] Here, the application of the moment method to
Brownian coagulation of fractal agglomerates,[34] which
are often involved in the synthesis of nanoparticles, is
addressed as an example for the continuum regime where
the slip correction factor is equal to 1.
In the moment method, to represent a polydisperse
aerosol size distribution, the log-normal function (one of
the most commonly used mathematical forms for the
study of the dynamics of particles) is used. The size
distribution density function for particles whose radius is r
for the log-normal distribution is written as:

 ln2 fr=rg ðtÞg
nðr; tÞ ¼
r 2p ln sðtÞ
2 ln2 sðtÞ


where N(t) is the total number concentration of
particles, s(t) is the geometric standard deviation based
on particle radius, and rg(t) is the geometric number

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.

mean particle radius. For studying the coagulation
problem in which two particles collide to become a
particle whose volume is the sum of the two volumes,
it is convenient to rewrite Eq. 33 in terms of particle volume:

 ln2 fv=vg ðtÞg
nðv; tÞ ¼
3v 2p ln sðtÞ
18 ln2 sðtÞ


where vg is the geometric number mean particle
volume. If one obtains the time evolution of the
three parameters N(t), s(t), and vg(t), the particle size
distribution of the coagulating aerosol of interest for
any time t can be constructed using Eq. 34.
The kth moment of the particle size distribution is
written as:
Mk ¼



vk nðv; tÞdv



where k is an arbitrary real number. According to the
properties of a log-normal function, any moment can be
written in terms of M0, vg, and s as follows:
Mk ¼

M0 vkg

9 2 2
k ln s


If Eq. 36 is written for k= 0, 1, and 2, and subsequently
solved for vg and s in terms of M0, M1, and M2, we have:

M0 M2
ln s ¼ ln

vg ¼





M0 M2

The collision kernel of fractal agglomerates bF(v,v)
covering the continuum regimes is represented by the
following expression:[35]
bF ðv; vÞ ¼ Kco ðv



þ v






where Kco is defined by Eq. 3, and Df is the mass fractal
dimension, which varies between 1 and 3.[36] Substituting
Eq. 39 into Eq. 5 and integrating from 0 to 1, one can
obtain the following equations using Eq. 35:
¼ Kco ðM02 þ M1=Df M1=Df Þ


¼ 0


¼ 2Kco fM12 þ MðDf 1Þ=Df MðDf þ1Þ=Df g


Eq. 41 merely indicates that M1=const. Substituting Eq. 36
for the moments appearing in the right-hand side of
Eqs. 40 and 42, and substituting Eqs. 37 and 38 thereafter, we have the following two equations for k=0 and
2, respectively:

ð2þð1=D2f ÞÞ 2=D2f
¼ Kco M02 þ M0
M2 f


1=D2 ð2ð2=D2f ÞÞ 1=D2f
¼ 2Kco M12 þ M0 f M1


The governing equation has just been converted into a set
of three first-order ODEs. Eqs. 41, 43, and 44 can be
solved using any standard numerical package for solving
first-order ODEs. After M0, M1, and M2 are solved from
Eqs. 43, 41, and 44, respectively, s and vg can be
computed using Eqs. 37 and 38. Subsequently, the size
distribution of the fractal agglomerates for any time can be
constructed using Eq. 34.
Coagulation in Nanoparticle Synthesis
Among the most recent developments in the theoretical
description of gas-to-particle conversion process is the
simultaneous modeling of precursor decomposition, coagulation, and sintering processes in the aerosol, originally reported by Koch and Friedlander[20] and Kobata et
al.,[37] and refined further by Xiong and Pratsinis,[19]
Xiong et al.,[38] and Tsantilis and Pratsinis[39] using elaborate two-dimensional sectional models of the population balance equation. In chemical vapor synthesis
(CVS), particles pass through the complete temperature profile of a hot wall reactor together with the gas
stream. The CVS technique is based on the process of
chemical vapor deposition (CVD), which is widely
employed to prepare coatings at a high level of control
of the growth parameter and, consequently, of the
microstructure. As the process is very important for
basic research and industrial production, the conditions
for CVD growth have been determined for many
material systems. The formation process of nanoparticles
in the gas phase has been studied intensively both
experimentally and theoretically. Many kinetic models
exist to describe the dependence of the particle size on
various synthesis parameters such as partial and total
pressure, temperature, etc. It is of particular interest to
study the particle formation on an atomic scale to understand the diffusional processes that lead to coagulation and particle rearrangement on the short time scale
of their formation. Molecular dynamics (MD) simulation
is used to study the particle formation and the coagulation/sintering processes.

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.

Therefore the coagulation of particles suspended in a gas
or a liquid strongly influences the particle size distribution
and is of fundamental interest in a wide range of applications in science and engineering. In this chapter, some
theories of coagulation are reviewed.
The coagulation of a monodisperse aerosol was studied
for Brownian coagulation by Smoluchowski[1] and the
change of particle number concentration with respect to
time was provided. The general coagulation equation of
polydisperse aerosol particles was introduced and the
collision kernels for Brownian, gravitational, laminar
shear, turbulent, and electrostatic coagulations were
presented. In case of Brownian coagulation, the kinetic
theory and the continuum diffusion theory were used to
derive the collision kernel for the free molecule regime and
the continuum regime, respectively, and the two theories
were brought together by flux matching to produce the
kernel for transition regime. At the end of this chapter,
various solution techniques were introduced including the
sectional method, the self-preserving solution, and the
moment method. The sectional method provides the most
accurate prediction on the size distribution changes. The
self-preserving size distribution theory presents the asymptotic size distribution. The moment method has the
advantage of simplicity while providing important information on the change of the size distribution of aerosol.

We are grateful to Dr. Sung-Hoon Park (University of
British Columbia) and Mr. Xiang Rongbiao for their
valuable comments on the manuscript.




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Cohen, E.R.; Vaughan, E.U. Approximate solution
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Binkowski, F.S. Modal Aerosol Dynamics Modeling, EPA Report 600/3-91/020; 1991.
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Simulation of aerosol agglomeration in the free
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Basic Nanostructured Catalysts


Robert J. Davis

University of Virginia, Charlottesville, Virginia, U.S.A.



Solid bases catalyze a wide variety of chemical transformations (e.g., condensations, alkylations, cyclizations,
and isomerizations). However, compared with their solid
acid analogues, they have received relatively little
attention from the industrial and academic communities.
The search for novel solid bases that catalyze reactions
with high product selectivity, high reaction rate, and low
deactivation rate is an ongoing process. The following text
describes current research trends in the design and
utilization of nanostructured solid bases composed mainly
of supported metals and metal oxides.

Basicity, in the context of the following discussion, can
be defined in the Lewis sense as the donation of electrons
from a solid surface to an acceptor species. Thus for a
typical solid base such as a metal oxide, the exposed
metal cation is regarded as a Lewis acid site and the
exposed oxygen atom is regarded as a Lewis base site, as
illustrated in Fig. 1. Because basicity is related to the
electronic charge on the oxygen atom, it is important to
understand how this charge depends on composition. One
very simple method that is often used to compare
structurally similar compounds is based on the intermediate electronegativity principle of Sanderson. The
Sanderson intermediate electronegativity (SE,int) of a
solid is calculated from the mean of the individual
electronegativities of the elements present according to
Eq. 1, where SE,Z is the individual electronegativity of
element Z and x is the atomic ratio of element Z present.
The general idea is that an equalization of the electronegativities in a compound results from electron transfer
that occurs in the formation of the compound.[3] The
calculation of the intermediate electronegativity takes
into account only the composition of the compound,
ignoring the effect of structure and surface composition.
From the Sanderson intermediate electronegativity, the
partial negative charge on oxygen (dq)O can be calculated
from Eqs. 2 and 3. A high partial negative charge on
oxygen indicates strong basicity of the oxide surface:
P 1
SE;int ¼ ð SxE;Z Þð xÞ

The earliest use of alkalis was probably about 4000 B.C.
during the New Stone Age period in the production of
quicklime (CaO) by roasting limestone (CaCO3).[1] The
early uses of quicklime were for the removal of fat and
hair from leather and in the production of cement.
Around 3000 B.C., a dilute solution of potash (K2CO3)
produced by leaching ashes from wood fires was found
to have cleaning powers.[1] Adding fat to the solution
likely formed the first soap. At about the same time,
evidence shows that glass containing sodium carbonate
was also being produced. These early uses of bases
preceded the common uses of acids by several thousand
years. The first commonly used acid was probably acetic
acid because it was used to prepare white lead pigment
around 300–400 B.C.[1]
Despite the tremendous lead time in technology with
bases, applications in catalysis by solid bases lag far
behind that by solid acids. Tanabe and Holderich[2]
recently performed a statistical survey of industrial
processes using solid acids, solid bases, and acid–base
bifunctional catalysts and have counted 103, 10, and 14
industrial processes for these types of catalysts, respectively. The number of acid-catalyzed processes outnumbers those catalyzed by solid bases by an order of
magnitude. However, as novel base materials are discovered and new base-catalyzed reactions are found to be
commercially relevant, new processes are sure to appear.
Dekker Encyclopedia of Nanoscience and Nanotechnology
DOI: 10.1081/E-ENN 120009435
Copyright D 2004 by Marcel Dekker, Inc. All rights reserved.

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.

DSE;O ¼ 2:08ðSE;O Þ1=2

ðdq ÞO ¼

ðSE;int  SE;O Þ



Typical measurements of basicity are obtained by titration
with indicators having a wide range of pKa values. For
a reaction of an acid indicator BH with a solid base B*
(Eq. 4), the Hammett basicity function H is defined by
Eq. 5, where [BH] is the concentration of the indicator
and [B] is the concentration of its conjugate form. One

formed under identical experimental conditions (carrier
gas flow, heating rate, and sample size) so that a qualitative
comparison can be made between samples. During a TPD
experiment, the amount of desorbed molecules is often
monitored by mass spectrometry and the surface interactions are explored with IR spectroscopy.
Fig. 1 Schematic illustration of Lewis acid and Lewis base
sites on a metal oxide surface. M represents a surface metal
cation and O represents a surface oxygen anion.

problem with using adsorbed indicators to evaluate basicity is the interference of indicator reactions that are not
because of acid–base chemistry. In addition, evidence of
reaction is often provided by a color change, which requires the use of colorless catalysts. Clearly, there is a need
for other methods to probe surface base sites:
BH þ B () B þ B Hþ
H ¼ pKa þ log




One commonly used method to study solid base sites
involves adsorption of a probe molecule followed by
examination with infrared (IR) spectroscopy. Infrared
spectrometric studies of various probe molecules adsorbed
on solid bases have been reviewed by Lavalley.[4] One of
the major problems with this technique is that many of the
commonly used probe molecules decompose or react on
interaction with the basic site, and thus do not effectively
interrogate the catalyst surface. For example, pyrrole has
been found to dissociatively chemisorb on highly basic
metal oxides such as ThO2 and CeO2, forming the C4H4N
pyrrolate anion.[4] A probe molecule should undergo
specific chemical interactions with the base sites without
dramatically altering the catalyst surface. Therefore the
search for a unique, widely applicable adsorbate molecule
to probe the surface base sites of heterogeneous catalysts is
a daunting process. No single probe is universally adept at
characterizing the active sites on all basic solids. Carbon
dioxide is probably the most widely used probe for surface
basicity because of its stability and ease of handling.
Because carbon dioxide is a weakly acidic molecule, it
selectively adsorbs on base sites. However, carbon dioxide
adsorption on metal oxides results in many different types
of surface species, which can complicate interpretation.
Temperature-programmed desorption (TPD) of adsorbed probe molecules can also be used to measure the
number and strength of sites found on solid base catalysts.
Because strongly bound probe molecules have high
adsorption energies, increased temperatures are necessary
to desorb these species. Experiments are typically per-

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.

Alkali metals and metal oxides are among the strongest
bases known. However, these materials typically have a
very low surface area that limits their ability to be
effective catalysts. New material processing technology
can be used to create bulk materials with very high
surface-to-volume ratios (i.e., very small crystallite sizes),
but the resulting fine powders become very difficult to use
as heterogeneous catalysts. Therefore basic metals and
metal oxides are often supported on high surface area
carriers to achieve high dispersion of the base sites
without sacrificing ease of handling.
To illustrate the concept of supporting alkali metal
oxides on supports, Doskocil et al.[5] loaded rubidium onto
magnesia, titania, alumina, carbon, and silica by decomposition of an impregnated acetate precursor at 773 K.
Results from x-ray absorption spectroscopy indicated that
the local structure around Rb was highly dependent on the
support composition. For example, the Rb–O distance was
significantly shorter on carbon and silica compared with
more basic carriers. Results from CO2 stepwise TPD
showed that Rb/MgO possessed strongly basic sites that
were not present on pure MgO. However, the basic sites
formed by Rb addition to the other supports were weaker
than those on Rb/MgO. The TPD experiments were
complemented by adsorption microcalorimetry of both
ammonia (titrates acid sites) and carbon dioxide (titrates
base sites) on the same samples.[6] Microcalorimetry
revealed that incorporation of rubidium onto the supports
neutralized acid sites and created new base sites. Decomposition of 2-propanol at 593 K was used as a probe
reaction to relate catalytic activity to surface basicity.[5]
As anticipated, Rb/MgO and MgO were highly active and
selective for dehydrogenation of alcohol. The addition of
Rb to alumina and titania significantly decreased the
activity of the support oxides for the acid-catalyzed
dehydration of 2-propanol. Both reactivity and characterization results on Rb/SiO2 were consistent with the
formation of a highly disordered, weakly basic, surface
silicate phase that exhibited little activity for alcohol
decomposition. Evidently, highly basic rubidium oxide
reacted with the silica surface, probably through surface
hydroxyl groups, to form rubidium silicate. Because the
overall rate of acetone formation from 2-propanol

correlated with the ranking of support basicity, as
evaluated from the Sanderson intermediate electronegativity principle, strongly basic alkali-containing catalysts
should utilize basic carriers to minimize alkali–support
interactions that lower base strength.
It has become clear that to have strongly basic catalysts
on conventional supports, the carrier should be preconditioned with a base to create a surface phase that can
accommodate a strong base. Another strategy used to
support bases involves incorporation into the nanopores of
a crystalline material such as a zeolite. The following
discussion focuses on the most commonly studied
nanostructured materials that have been explored as
supports for base catalysts.
Zeolites are highly porous aluminosilicates that are
constructed from TO4 tetrahedra (T = tetrahedral atom,
e.g., Si, Al), with each apical oxygen atom shared with an
adjacent tetrahedron. When tetrahedra containing Si4+ and
Al3+ are connected to form a three-dimensional zeolite
framework, a negative charge is associated with each Al3+
atom. The negative framework charge is balanced by an
exchangeable cation to achieve electrical neutrality. Some
of the countercations in the zeolite pores can be readily
exchanged with other cations, altering the acid–base
character of the zeolite framework. Exchanging zeolites
with a less electronegative charge-balancing cation such
as cesium creates a more basic zeolite. An excellent
review of basic zeolites was written by Barthomeuf.[7]
The main feature that makes zeolites very interesting
nanostructured supports is that their pores are uniform in
size and are in the same size range as small molecules.
Zeolites are molecular sieves because they discriminate
molecules based on size. Molecules smaller than the pore
size are adsorbed in the crystal interior, whereas those that
are larger are excluded. This feature of zeolites creates a

unique reaction environment for supported base catalysts,
if the base sites are located in the micropores.
Alkali metal oxides in zeolite pores
Fig. 2 illustrates a typical procedure for incorporating
alkali metal oxide clusters into the pores of zeolite X.
Zeolite X is of the faujasite type with a Si/Al ratio ranging
from 1 to 1.5. The rather high content of aluminum in the
structure indicates that the framework has a substantial
negative charge that is balanced by exchangeable cations.
The exchangeable cations are usually replaced with heavy
alkali metal cations prior to impregnating an alkali metal
compound. In Fig. 2, an aqueous solution of cesium
acetate is impregnated into the micropores of Csexchanged X zeolite. Thermal treatment in air is sufficient
to decompose the acetate precursor and leave behind
alkali metal oxide in the pores of the zeolite.
The basic properties of cesium oxide occluded in the
pores of zeolite X have been characterized by a wide
variety of methods, including CO2 adsorption microcalorimetry,[8,9] CO2 TPD,[9–14] IR spectroscopy of adsorbed
CO2,[10,15] nuclear magnetic resonance (NMR) spectroscopy,[10,16,17] and x-ray absorption spectroscopy.[15] For
basic zeolites containing occluded Cs oxide that have been
thermally activated at about 773 K, most of the CO2
desorbed with a peak temperature less than 573 K. This
result suggests a rather moderate base strength for the
occluded Cs species. In fact, results from CO2 adsorption
microcalorimetry indicated that most of the adsorption
sites at 373 K are characterized by an adsorption enthalpy
of about  100 kJ mol1, which is hundreds of kilojoules
lower in magnitude than that anticipated for adsorption of
CO2 on a stoichiometric alkali metal oxide.
The stoichiometry of the occluded alkali metal oxide
cluster is still an open question. Lasperas et al.[13,14] used
TPD of CO2 from cesium oxide loaded onto CsX zeolite
to measure an adsorption stoichiometry of one CO2

Fig. 2 Synthesis procedure for preparing cesium oxide species in the supercages of Cs-exchanged zeolite X.

Copyright © 2004 by Marcel Dekker, Inc. All rights reserved.


desorbed per occluded pair of Cs atoms. Because that ratio
matches the ideal reaction stoichiometry of Cs2O plus
CO2 to form Cs2CO3, they concluded that the oxide in the
zeolite pores was likely Cs2O. In contrast, Bordawekar
and Davis[8] reported results from CO2 adsorption
microcalorimetry that indicated an adsorption stoichiometry of one CO2 adsorbed per four occluded Cs atoms. An
explanation for the difference is not readily apparent.
What appears to be consistent from the various works is
that cesium is fairly well distributed throughout the zeolite
pores at loadings below about two cesium atoms per
supercage. At higher loadings, cesium deposits on the
external surface of the zeolite.
The rather moderate base strength evaluated by CO2
adsorption microcalorimetry suggests that the occluded Cs
is not in a form that is typical of a stoichiometric alkali
oxide. Krawietz et al.[18] recently reported that they could
not successfully prepare bulk-phase Cs2O by conventional
chemical methods, whereas stoichiometric lighter alkali
metal oxides could be prepared. The heavy alkali
preferred instead to form higher oxides. Their intriguing
result points to the possibility that higher oxides such as
cesium peroxide and cesium superoxide might be present
in zeolite-supported cesium oxide samples. Indeed, higher
oxides of Cs should exhibit less base strength than the
stoichiometric oxide Cs2O. Yagi and Hattori[19] have
shown that dioxygen retains its molecular identity when
adsorbed on thermally activated cesium oxide clusters
occluded in zeolite X. In other words, exposure of the
material to 18O2 yields both 18O2 and 16O2 in the gas
phase, with only traces of 18O16O being observed. A
mechanism involving the formation of peroxides was
invoked to explain the isotopic distribution. Although the
authors of that study speculate that the zeolite initially
contained Cs2O clusters, the presence of peroxides should
not be ruled out.
Intrazeolitic clusters of cesium oxide species are active
in a variety of base-catalyzed reactions. For example, the
decomposition of 2-propanol to acetone was catalyzed by
cesium oxide species in Y zeolite at a rate (based on
surface area) comparable to MgO.[20] In general, solid
bases catalyze the dehydrogenation of 2-propanol to

acetone, whereas solid acids typically catalyze dehydration to propene. Another reaction catalyzed by basic
materials is the cycloaddition of CO2 to an oxirane such as
ethylene oxide. The rather moderate adsorption strength
of CO2 on zeolites containing occluded alkali metal
oxides indicates that CO2 might be useful as a reagent in
catalytic reactions on