Science at the Nanoscale: An Introductory Textbook

224 Pages·2009·7.031 MB·English

by  Andrew T. S. Wee, Chorng Haur Sow, Chin Wee Shong

Published by
Pan Stanford Publishing Pte. Ltd.
Penthouse Level, Suntec Tower 3
8 Temasek Boulevard
Singapore 038988
Email: [email protected]
Web: www.panstanford.com
British Library Cataloguing-in-Publication Data
A catalogue record for this book is available from the British Library.
SCIENCE AT THE NANOSCALE
An Introductory Textbook
Copyright © 2010 by Pan Stanford Publishing Pte. Ltd.
All rights reserved. This book, or parts thereof, may not be reproduced in any form
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ISBN-13978-981-4241-03-8
ISBN-10981-4241-03-2
Printed in Singapore.
Rhaimie - Science at the Nanoscale.pmd 1 6/11/2009, 12:03 PM
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Acknowledgements
WegratefullyacknowledgeourstudentsinSP2251andUPC2206
fortheirinputsandfeedbackduringtheteachingofthesecourses,
the materials of which eventually led to the development of this
book. We also thank our graduate students from the Nano-
materials Synthesis Laboratory, Colloid Laboratory and Surface
ScienceLaboratoryatNUSfortheuseoftheirexperimentalresults
in the book. Finally, we are grateful to the many laboratory
officers, research fellows and colleagues from the NUS Physics
andChemistrydepartments,andthe NUSNanoscience&Nano-
technologyInitiative,aswellasourfamilies,fortheirsupportand
understanding. Ittooktwoyearstoputthisbooktogether,amidst
ourheavycommitments.
June12,2009 7:54 RPS:PSP0007-Science-at-Nanoscale FM
vi
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Preface
Nanotechnologyisoneofthemostimportantgrowthareasinthe
21stcentury.Nanoscience,thescienceunderpinningnanotechnol-
ogy,isamultidisciplinarysubjectcoveringatomic,molecularand
solidstatephysics,aswellasmuchofchemistry. Nanostructures
are known to exhibit novel and improved material properties.
Fundamentally,thesearisebecausethephysicalaswellaschemi-
calpropertiesareverydifferentwhendimensions arereducedto
the nanometer range. This book thus aims to introduce the vari-
ousbasicprinciplesandknowledgeneededforstudentstounder-
standscienceatthenanoscale.
Manyideasproposedinnanotechnologyarefrontierandfutur-
istic, although some have immediate technological applications.
Thefundamentalscientificprinciplesofallnanotechnologyappli-
cations,however,aregroundedinphysicsandchemistry.
Nanoscience and nanotechnology degree programmes are
beingincreasinglyofferedbymoreandmoreuniversitiesaround
the world, especially in Australia and Europe.1 A conventional
undergraduatestudyofascienceandengineeringdisciplinenor-
mallyspecialisesinthefinalyear(s),butnanotechnologycurricula
oftenaimtoconfrontstudentsfromtheirfirstorsecondyearswith
the essence and interdisciplinarity of nanoscience and nanotech-
nology. Byintroducingtheideasandapplicationsofnanoscience
early, students receive a coherent overview of nanoscience to
motivate them to learn the necessary basics in the traditional
science disciplines of physics, mathematics, chemistry, materials
science, biology and medicine. Real interdisciplinarity can be
achievedbycombiningthebreadthofnanosciencewiththedepth
ineachdiscipline.
1Wikipedia (under entry: “Nanotechnology Education”, http://en.wikipedia.
org/wiki/Nanotechnology education) states the first programme involving
nanotechnologywasofferedbytheUniversityofToronto,wherenanotechnology
could be taken as an option within their Engineering Science programme.
Interestingly, Wikipedia indicatesthat todate, Australia leads theworld with
nine universities offering bachelors degree programmes, followed closely by
Europewithaboutseven
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viii Preface
Therearesomerecurringthemesinnanoscienceandnanotech-
nologyeducation:
• The basic foundational disciplines are crucially important in any
nanotechnologyprogram;
• Thenanoscalehasalwaysbeenimportantinchemistry,physics,
biologyandengineering,butwiththeadventofnewtoolsand
technologies, the nanoscale is now openly visible, comprehen-
sibleandmanipulable;
• It is critical for students to recognize connections between the
differentscientificandengineeringdisciplines.
The metrics for identifying success in nanotechnology programs
aretypicallytheacquiringofmultiscalescientificknowledge,and
theabilityof theprogramstokeepup-to-datewith thelatestsci-
entificdiscoveries.
There are currently numerous specialised nanoscience and
nanotechnology-relatedtextsormonographsatthegraduateand
senior undergraduate levels. This textbook is targeted at the
junior undergraduate levels or as a reference text for advanced
learnersatpre-universityandseniorhighschool,andhasevolved
from the authors’ own teaching of the following modules at the
NationalUniversityofSingapore:
• GEK1509IntroductiontotheNanoworld
• UPC2206NanoscaleScienceandTechnology
• SP2251ScienceattheNanoscale
Theauthors’ownresearchexpertisecoveradiverserangeofareas
including nanomaterials chemistry and self-assembly (Chin Wee
Shong), colloids, nanowires, optical tweezers and atomic force
microscopy (Sow Chorng Haur), surface science and scanning
tunneling microscopy (Andrew T S Wee). This book therefore
aims to be a practical and user friendly textbook that could be
adopted in introductory undergraduate courses in nanoscience
and nanotechnology, materials science and engineering, physics
andchemistry.
Supplementarymaterials,includingsolutionstoexercises,forthis
textbookareavailableatwww.panstanford.com/nanotextbook.
ChinWeeShong,SowChorngHaur,AndrewTSWee
NationalUniversityofSingapore
2009
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About the Authors
Chin Wee Shong is an Associate Professor of
Chemistry at the National University of
Singapore.Herresearchinterestsincludethestudies
ofnanostructuresandtheirassemblies,themecha-
nismofsize-,shape-andphase-controlledformation
of nanocrystals, solution and templated synthe-
sis of various types of nanomaterials and hybrid
materials.Shehasvastexperienceintheteachingof
undergraduatephysical chemistry courses, includ-
ing topics such as spectroscopy, kinetics, electro-
chemistry, solid state as well as surface chemistry.
Sow Chorng Haur is an Associate Professor of
PhysicsattheNationalUniversityofSingapore.His
researchinterestsincludethestudiesofnanomate-
rialssystemssuchascarbonnanotubesandnanos-
tructuredmetallicoxides,developmentofnanofab-
rication techniques such as focused laser beam
nanofabrication, studies of colloidal systems, and
developmentoftheopticaltweezerstechniquesfor
contactless manipulation of micro- and nanoscale
objects.
Andrew T S Wee is a Professor of Physics at the
National University of Singapore. His research
interests include surface nanostructure formation,
molecular self-assembly on nanotemplates, syn-
chrotronandscanningtunnelingmicroscopy stud-
iesofsurfacesandinterfaces,grapheneandrelated
nanomaterials.Heisintheeditorialboardofseveral
journals,includingAppliedPhysicsLetters-Journal
ofAppliedPhysics, SurfaceandInterfaceAnalysis, In-
ternationalJournalofNanoscience,SurfaceReviewand
Letters,andCurrentNanoscience.HeisalsoPastPres-
ident&FellowoftheInstituteofPhysicsSingapore,
andaFellowoftheInstituteofPhysics(UK).
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Table of Contents
Acknowledgements v
Preface vii
AbouttheAuthors ix
1. IntroductionandHistoricalPerspective 1
1.1 TheDevelopmentofNanoscaleScience . . . . . . 1
1.2 TheNanoscale . . . . . . . . . . . . . . . . . . . . . 7
1.3 ExamplesofInterestingNanoscienceApplications 8
2. ClassicalPhysicsattheNanoscale 19
2.1 MechanicalFrequency . . . . . . . . . . . . . . . . 20
2.2 Viscosity . . . . . . . . . . . . . . . . . . . . . . . . 24
2.3 BrownianMotionofNanoscaleObjects . . . . . . 25
2.4 MotionattheNanoscale . . . . . . . . . . . . . . . 27
3. BriefReviewofQuantumMechanics 31
3.1 BasicQuantumPhysicsandQuantumConfinement 31
3.2 BasicPostulatesofQuantumMechanics . . . . . . 35
3.3 Hydrogen-LikeAtoms: Orbitalsand
AtomicStructures . . . . . . . . . . . . . . . . . . . 49
3.4 Spin . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
4. FromAtomsandMoleculestoNanoscaleMaterials 61
4.1 AtomsandthePeriodicTableofElements . . . . . 61
4.2 MoleculesandMolecularInteractions . . . . . . . 64
4.3 FromAtomstoSolidMaterials . . . . . . . . . . . 76
4.4 FromMoleculestoSupramolecules . . . . . . . . . 85
5. SurfacesattheNanoscale 93
5.1 SurfaceEnergy . . . . . . . . . . . . . . . . . . . . 93
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TableofContents xi
5.2 SurfaceReactivityandCatalysis . . . . . . . . . . 100
5.3 SurfaceStabilisation . . . . . . . . . . . . . . . . . 102
6. Low-DimensionalNanostructures 109
6.1 From3Dto0DNanostructures . . . . . . . . . . . 109
6.2 ElectronTransportPropertiesinLow
DimensionalSystems . . . . . . . . . . . . . . . . . 122
6.3 QuantumDots,QuantumWires . . . . . . . . . . 131
7. FormationandSelf-AssemblyattheNanoscale 141
7.1 SomeBasicThermodynamicDefinitions . . . . . . 141
7.2 TheBottom-UpApproach . . . . . . . . . . . . . . 146
7.3 TheSelf-AssemblyProcesses . . . . . . . . . . . . 150
8. NanotoolsandNanofabrication 159
8.1 OpticalMicroscopy . . . . . . . . . . . . . . . . . . 159
8.2 ElectronMicroscopy . . . . . . . . . . . . . . . . . 162
8.3 ScanningProbeMicroscopy . . . . . . . . . . . . . 176
8.4 OpticalTweezers . . . . . . . . . . . . . . . . . . . 190
9. FutureTrends 201
9.1 NanotechnologyandtheDevelopingWorld . . . . 202
9.2 BeyondMoore’sLaw . . . . . . . . . . . . . . . . . 203
9.3 SpintronicsandSurfaceChemistry . . . . . . . . . 204
9.4 CarbonElectronics . . . . . . . . . . . . . . . . . . 206
Index 211
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