In Situ Transmission Electron Microscopy Studies of Carbon Nanotube Nucleation Mechanism and Carbon Nanotube-Clamped Metal Atomic Chains

In Situ Transmission Electron Microscopy Studies of Carbon Nanotube Nucleation Mechanism and Carbon Nanotube-Clamped Metal Atomic Chains PDF Author: Dai-Ming Tang
Publisher: Springer Science & Business Media
ISBN: 3642372597
Category : Technology & Engineering
Languages : en
Pages : 131

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Book Description
Using an in situ transmission electron microscopy (TEM) approach to investigate the growth mechanism of carbon nanotubes (CNTs) as well as the fabrication and properties of CNT-clamped metal atomic chains (MACs) is the focus of the research summarized in this thesis. The application of an in situ TEM approach in the above-mentioned research provides not only real-time observation but also monitored machining and structural evolvement at the atomic level. In this thesis, the author introduces a CNT tubular nano furnace that can be operated under TEM for investigation of the CNT nucleation mechanism. By studying the nucleation process of CNTs in the presence of various catalysts, including iron-based metallic catalysts and silicon oxide-based non-metallic catalysts, the physical states of the catalysts as well as the nucleation and growth process of CNTs are revealed. Based on the understanding of the nucleation mechanism, the author proposes a hetero-epitaxial growth strategy of CNTs from boron nitride, which provides a new route for the controllable growth of CNTs. In addition, the author presents an electron beam-assisted nanomachining technique and the fabrication of a CNT-clamped MAC prototype device based on this technique. The formation process of CNT-clamped Fe atomic chains (ACs) can be monitored with atomic resolution. The demonstrated quantized conductance and uninfluenced half-metallic properties of Fe ACs indicate that CNTs can be promising nanoscale electrodes or interconnectors for the linking and assembly of nano and subnano structures.

In Situ Transmission Electron Microscopy Studies of Carbon Nanotube Nucleation Mechanism and Carbon Nanotube-Clamped Metal Atomic Chains

In Situ Transmission Electron Microscopy Studies of Carbon Nanotube Nucleation Mechanism and Carbon Nanotube-Clamped Metal Atomic Chains PDF Author: Dai-Ming Tang
Publisher: Springer Science & Business Media
ISBN: 3642372597
Category : Technology & Engineering
Languages : en
Pages : 131

Get Book Here

Book Description
Using an in situ transmission electron microscopy (TEM) approach to investigate the growth mechanism of carbon nanotubes (CNTs) as well as the fabrication and properties of CNT-clamped metal atomic chains (MACs) is the focus of the research summarized in this thesis. The application of an in situ TEM approach in the above-mentioned research provides not only real-time observation but also monitored machining and structural evolvement at the atomic level. In this thesis, the author introduces a CNT tubular nano furnace that can be operated under TEM for investigation of the CNT nucleation mechanism. By studying the nucleation process of CNTs in the presence of various catalysts, including iron-based metallic catalysts and silicon oxide-based non-metallic catalysts, the physical states of the catalysts as well as the nucleation and growth process of CNTs are revealed. Based on the understanding of the nucleation mechanism, the author proposes a hetero-epitaxial growth strategy of CNTs from boron nitride, which provides a new route for the controllable growth of CNTs. In addition, the author presents an electron beam-assisted nanomachining technique and the fabrication of a CNT-clamped MAC prototype device based on this technique. The formation process of CNT-clamped Fe atomic chains (ACs) can be monitored with atomic resolution. The demonstrated quantized conductance and uninfluenced half-metallic properties of Fe ACs indicate that CNTs can be promising nanoscale electrodes or interconnectors for the linking and assembly of nano and subnano structures.

Advanced Transmission Electron Microscopy

Advanced Transmission Electron Microscopy PDF Author: Francis Leonard Deepak
Publisher: Springer
ISBN: 3319151770
Category : Technology & Engineering
Languages : en
Pages : 281

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Book Description
This book highlights the current understanding of materials in the context of new and continuously emerging techniques in the field of electron microscopy. The authors present applications of electron microscopic techniques in characterizing various well-known & new nanomaterials. The applications described include both inorganic nanomaterials as well as organic nanomaterials.

Carbon Nanotubes

Carbon Nanotubes PDF Author: M. Endo
Publisher: Elsevier
ISBN: 008054553X
Category : Science
Languages : en
Pages : 200

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Book Description
Carbon nanotubes have been studied extensively in relation to fullerenes, and together with fullerenes have opened a new science and technology field on nano scale materials. A whole range of issues from the preparation, structure, properties and observation of quantum effects in carbon nanotubes in comparison with 0-D fullerenes are discussed. In addition, complementary reviews on carbon nanoparticles such as carbon nano-capsules, onion-like graphite particles and metal-coated fullerenes are covered. This book aims to cover recent research and development in this area, and so provide a convenient reference tool for all researchers in this field. It is also hoped that this book can serve to stimulate future work on carbon nanotubes.

Carbon Nanotube and Related Field Emitters

Carbon Nanotube and Related Field Emitters PDF Author: Yahachi Saito
Publisher: John Wiley & Sons
ISBN: 3527632107
Category : Science
Languages : en
Pages : 551

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Book Description
Carbon nanotubes (CNTs) have novel properties that make them potentially useful in many applications in nanotechnology, electronics, optics and other fields of materials science. These characteristics include extraordinary strength, unique electrical properties, and the fact that they are efficient heat conductors. Field emission is the emission of electrons from the surface of a condensed phase into another phase due to the presence of high electric fields. CNT field emitters are expected to make a breakthrough in the development of field emission display technology and enable miniature X-ray sources that will find a wide variety of applications in electronic devices, industry, and medical and security examinations. This first monograph on the topic covers all aspects in a concise yet comprehensive manner - from the fundamentals to applications. Divided into four sections, the first part discusses the preparation and characterization of carbon nanotubes, while part two is devoted to the field emission properties of carbon nanotubes, including the electron emission mechanism, characteristics of CNT electron sources, and dynamic behavior of CNTs during operation. Part three highlights field emission from other nanomaterials, such as carbon nanowalls, diamond, and silicon and zinc oxide nanowires, before concluding with frontier R&D applications of CNT emitters, from vacuum electronic devices such as field emission displays, to electron sources in electron microscopes, X-ray sources, and microwave amplifiers. Edited by a pioneer in the field, each chapter is written by recognized experts in the respective fields.

Electron Microscopy of Nanotubes

Electron Microscopy of Nanotubes PDF Author:
Publisher: 清华大学出版社有限公司
ISBN: 9787302082132
Category : Nanostructure materials
Languages : en
Pages : 338

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Book Description
本书用英文的形式分析了纳米管电子显微。

Growing Carbon Nanotubes

Growing Carbon Nanotubes PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
In situ transmission electron microscope (TEM) video (accelerated 10 times) of nucleation and self-organization of a high-density carbon nanotube network from catalytic iron nanoparticles, forming a vertically aligned forest.

Carbon Nanotubes: From Basic Research to Nanotechnology

Carbon Nanotubes: From Basic Research to Nanotechnology PDF Author: Valentin N. Popov
Publisher: Springer Science & Business Media
ISBN: 1402045743
Category : Technology & Engineering
Languages : en
Pages : 270

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Book Description
It is about 15 years that the carbon nanotubes have been discovered by Sumio Iijima in a transmission electron microscope. Since that time, these long hollow cylindrical carbon molecules have revealed being remarkable nanostructures for several aspects. They are composed of just one element, Carbon, and are easily produced by several techniques. A nanotube can bend easily but still is very robust. The nanotubes can be manipulated and contacted to external electrodes. Their diameter is in the nanometer range, whereas their length may exceed several micrometers, if not several millimeters. In diameter, the nanotubes behave like molecules with quantized energy levels, while in length, they behave like a crystal with a continuous distribution of momenta. Depending on its exact atomic structure, a single-wall nanotube –that is to say a nanotube composed of just one rolled-up graphene sheet– may be either a metal or a semiconductor. The nanotubes can carry a large electric current, they are also good thermal conductors. It is not surprising, then, that many applications have been proposed for the nanotubes. At the time of writing, one of their most promising applications is their ability to emit electrons when subjected to an external electric field. Carbon nanotubes can do so in normal vacuum conditions with a reasonable voltage threshold, which make them suitable for cold-cathode devices.

Point Defects in Carbon Nanostructures Studied by In-situ Electron Microscopy

Point Defects in Carbon Nanostructures Studied by In-situ Electron Microscopy PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
In the present work, the formation and migration of point defects induced by electron irradiation in carbon nanostructures, including carbon onions, nanotubes and graphene layers, were investigated by in-situ TEM. The mobility of carbon atoms normal to the layers in graphitic nanoparticles, the mobility of carbon interstitials inside SWCNTs, and the migration of foreign atoms in graphene layers or in layers of carbon nanotubes were studied. The diffusion of carbon atoms in carbon onions was investigated by annealing carbon onions and observing the relaxation of the compressed clusters in the temperature range of 1200 - 2000oC. An activation energy of 5.0±0.3 eV was obtained. This rather high activation energy for atom exchange between the layers not only prevents the exchange of carbon atoms between the layers at lower temperature but also explains the high morphological and mechanical stability of graphite nanostructures. The migration of carbon atoms in SWCNTs was investigated quantitatively by cutting SWCNT bundles repeatedly with a focused electron beam at different temperatures. A migration barrier of about 0.25 eV was obtained for the diffusion of carbon atoms inside SWCNTs. This is an experimental confirmation of the high mobility of interstitial atoms inside carbon nanotubes, which corroborates previously developed theoretical models of interstitial diffusivity. Individual Au and Pt atoms in one- or two-layered graphene planes and MWCNTs were monitored in real time at high temperatures by high-resolution TEM. The direct observation of the behavior of Au and Pt atoms in graphenic structures in a temperature range of 600 - 700°C allows us to determine the sites occupied by the metal atoms in the graphene layer and the diffusivities of the metal atoms. It was found that metal atoms were located in single or multiple carbon vacancies, not in off-plane positions, and diffused by site exchange with carbon atoms. Metal atoms showed a tendency to form clusters those.

Understanding Carbon Nanotubes

Understanding Carbon Nanotubes PDF Author: Annick Loiseau
Publisher: Springer
ISBN: 3540375864
Category : Science
Languages : en
Pages : 564

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Book Description
This volume presents the foundations of carbon nanotube science, reviewing recent developments and prospects for practical application. Each chapter summarizes relevant concepts from physics, chemistry or materials science, followed by detailed reports on topics including polymorphism and mircostructure of carbon; synthesis and growth; structural analysis by electron microscopy; spectroscopic methods; electronic structure; transport; mechanical and surface properties of nanotubes and composites.

Aligned Carbon Nanotubes

Aligned Carbon Nanotubes PDF Author: Zhifeng Ren
Publisher: Springer Science & Business Media
ISBN: 3642304907
Category : Science
Languages : en
Pages : 310

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Book Description
This book gives a survey of the physics and fabrication of carbon nanotubes and their applications in optics, electronics, chemistry and biotechnology. It focuses on the structural characterization of various carbon nanotubes, fabrication of vertically or parallel aligned carbon nanotubes on substrates or in composites, physical properties for their alignment, and applications of aligned carbon nanotubes in field emission, optical antennas, light transmission, solar cells, chemical devices, bio-devices, and many others. Major fabrication methods are illustrated in detail, particularly the most widely used PECVD growth technique on which various device integration schemes are based, followed by applications such as electrical interconnects, nanodiodes, optical antennas, and nanocoax solar cells, whereas current limitations and challenges are also be discussed to lay the foundation for future developments.