Carbon Nanowalls: Synthesis and Emerging Applications / Edition 1

by Mineo Hiramatsu, Masaru Hori

Overview

Representing the first text to cover this exciting new area of research, this book will describe synthesis techniques of CNWs, their characterization and various expected applications using CNWs. Carbon-nanowalls (CNWs) can be described as two-dimensional graphite nanostructures with edges comprised of stacks of plane graphene sheets standing almost vertically on the substrate. These sheets form a wall structure with a high aspect ratio. The thickness of CNWs ranges from a few nm to a few tens of nm. The large surface area and sharp edges of CNWs may prove useful for a number of applications such as electrochemical devices, field electron emitters, storage materials for hydrogen gas, catalyst support. In particular, vertically standing CNWs with a high surface-to-volume ratio, serve as an ideal material for catalyst support for fuel cells and in gas storage materials.

Product Details

ISBN-13:	9783211997178
Publisher:	Springer Vienna
Publication date:	08/02/2010
Edition description:	2010
Pages:	161
Product dimensions:	6.10(w) x 9.20(h) x 0.60(d)

Table of Contents

1 Introduction 1

1.1 Discovery of Two-Dimensional Carbon Nanostructures 1

1.2 Brief Description of Carbon Nanowalls 2

1.3 Research on Carbon Nanowalls 3

References 5

2 Preparation Methods 9

2.1 Microwave Plasma Enhanced Chemical Vapor Deposition 10

2.2 Inductively Coupled Plasma Enhanced Chemical Vapor Deposition 13

2.3 Capacitively Coupled Plasma Enhanced Chemical Vapor Deposition with Radical Injection 16

2.3.1 RF Plasma-Enhanced CVD with H Radical Injection 17

2.3.2 VHF Plasma-Enhanced CVD with H Radical Injection 19

2.4 Electron-Beam-Excited Plasma Enhanced Chemical Vapor Deposition 20

2.5 Hot Filament Chemical Vapor Deposition 23

2.6 Atmospheric Pressure Plasma 25

2.7 Sputtering 26

References 28

3 Physics of Carbon Nanowalls 31

3.1 Characterization of Carbon Nanowalls 31

3.1.1 SEM and TEM Observation 31

3.1.2 Raman Spectra of Carbon Nanowalls 34

3.1.3 Grazing Incidence In-Plane X-ray Diffraction 37

3.2 Electrical Properties of Carbon Nanowalls 39

3.2.1 Field Emission Properties of Carbon Nanowalls 39

3.2.2 Electrical Conduction of Carbon Nanowalls 40

3.2.3 Electrode for Electrochemistry 43

References 45

4 Fabrication of Carbon Nanowalls Using Radical Injection Plasma Enhanced CVD 49

4.1 Concept of Radical-Controlled Processing 49

4.2 RF Plasma-Enhanced CVD with H Radical Injection 51

4.2.1 Experimental Setup for RF Plasma-Enhanced CVD with H Radical Injection 51

4.2.2 Measurement of Radical Densities in the Capacitively Coupled Plasma Region 52

4.2.3 Effect of Carbon Source Gases and H Radicals on Carbon Nanowall Growth 53

4.2.4 Fabrication of Straight and Aligned Carbon Nanowalls with Regular Spacing 58

4.3 VHF Plasma-Enhanced CVD with H Radical Injection 60

4.3.1 Experimental Setup of VHF Plasma-Enhanced CVD with H Radical Injection 60

4.3.2 Chamber Cleaning for Carbon Nanowall Growth with High Reproducibility 61

4.3.3 Electrical Conduction Control of Carbon Nanowalls 68

4.3.4 Fabrication of Monolithic Self-Sustaining Graphene Sheets 73

References 79

5 Growth Mechanism of Carbon Nanowalls 81

5.1 Measurement of Radical Densities in the Plasma Used for the Fabrication of Carbon Nanowalls 81

5.1.1 Radicals in Microwave Plasma-Enhanced CVD with CH₄/H₂ Mixture 82

5.1.2 Radicals in Fluorocarbon Plasma with H Radical Injection 85

5.1.3 Discussion 89

5.2 Steady-State Growth of Carbon Nanowalls 91

5.2.1 RF Plasma-Enhanced CVD with H Radical Injection Employing C₂F₆/H₂ System 91

5.2.2 Inductively Coupled Plasma Enhanced CVD Employing CH₄/Ar System 92

5.2.3 Electron-Beam-Excited Plasma Enhanced CVD Employing CH₄/H₂ System 93

5.2.4 VHF Plasma-Enhanced CVD with H Radical Injection Employing C₂F₆/H₂ System 95

5.2.5 Discussion 96

5.3 Nucleation of Carbon Nanowalls 97

5.3.1 Investigation of Nucleation Stage of Carbon Nanowall Growth Employing C₂F₆/H₂ 97

5.3.2 Comparison of Carbon Nanowall Growth Employing C₂F₆/H₂ with and Without O₂ Gas Addition 101

5.3.3 Nucleation Model of Carbon Nanowalls 105

5.4 Nucleation Mechanism of Carbon Nanowall Growth Under Ion Irradiation 107

5.4.1 Carbon Nanowall Formation Using Multi-Beam CVD Technique 107

5.4.2 Effect of Ions on the Growth of Carbon Nanowalls 110

5.5 Area-Selective Growth of Carbon Nanowalls 112

References 114

6 Field Emission 117

6.1 Field Emission Properties of As-Grown Carbon Nanowalls 117

6.2 Surface Treatment for Improvement of Field Emission Properties 122

6.2.1 Surface Coating 123

6.2.2 Metal/Carbon Nanowall Composites 123

6.2.3 N₂ Plasma Treatment 125

References 127

7 Using Carbon Nanowalls as Templates 131

7.1 Fabrication of Nanostructured Materials Using Carbon Nanowalls as Templates 131

7.1.1 Decoration of Carbon Nanowalls 131

7.1.2 Fabrication of Nanostructured Materials on Carbon Nanowall Templates 132

7.2 Synthesis of Pt Nanoparticles on Carbon Nanowall Surface Using Supercritical Fluid Chemical Deposition 138

7.2.1 Introduction 138

7.2.2 Synthesis of Pt Nanoparticles by Plating 139

7.2.3 Synthesis of Pt Nanoparticles by Sputtering 140

7.2.4 Supercritical Fluids 141

7.2.5 Experimental Procedure of Metal-Organic Chemical Fluid Deposition Using Supercritical Carbon Dioxide 143

7.2.6 Characterization of Platinum Nanoparticles Formed by Metal-Organic Chemical Fluid Deposition Using Supercritical Carbon Dioxide 144

7.2.7 Mechanism of Platinum Nanoparticle Formation by Metal-Organic Chemical Fluid Deposition Using Supercritical Carbon Dioxide 148

7.3 Pattern Transfer from Carbon Nanowall into SiO₂ Film 151

References 155

8 Future Perspective for Emerging Applications Using Carbon Nanowalls 159

References 161