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Title: The effect of high-temperature annealing on the structure and electrical properties of well-aligned carbon nanotubes

Abstract

Systematic work has been performed on the effect of high-temperature annealing on structural defects and impurities of well-aligned carbon nanotubes (ACNTs) in this paper. ACNTs had been prepared by CVD process with ferrocene as catalyst and then the as-grown samples were experienced heat treatment (HT) from 1800 to 3000 deg. C. X-ray diffraction, Raman spectroscopy and electron dispersive spectroscopy (EDS), etc., have been used to analyze the effect of annealing. Results indicate that some impurities can be removed once annealing temperature exceeds vaporization point of corresponding metal or non-metal. Desorption of O should be attributed to reduced active sites of dangling covalent bonds after heat treatment. Specious discrepancy about interlayer spacing resulted from XRD and Raman tests show that although high-temperature heat treatment can remove in-plane defects of carbon nanotubes greatly, interlayer spacing between graphene shells could not be reduced effectively because of the special concentric cylindrical structure of nanotubes. Electrical resistivity of ACNTs block is about three orders higher than that of copper even after HT at 3000 deg. C, and the anisotropy of electrical properties increased once experienced heat treatment at increased temperature.

Authors:
 [1];  [2];  [2];  [2];  [2];  [2]
  1. Key Laboratory for Advanced Manufacturing by Materials Process, Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China). E-mail: gongqianming@mail.tsinghua.org.cn
  2. Key Laboratory for Advanced Manufacturing by Materials Process, Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China)
Publication Date:
OSTI Identifier:
21000604
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 42; Journal Issue: 3; Other Information: DOI: 10.1016/j.materresbull.2006.06.023; PII: S0025-5408(06)00275-3; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AFTER-HEAT; ANISOTROPY; ANNEALING; CARBON; CATALYSTS; CHEMICAL BONDS; CHEMICAL VAPOR DEPOSITION; COPPER; CRYSTAL DEFECTS; CYLINDRICAL CONFIGURATION; DESORPTION; ELECTRIC CONDUCTIVITY; EVAPORATION; FERROCENE; IMPURITIES; NANOTUBES; RAMAN SPECTROSCOPY; X-RAY DIFFRACTION

Citation Formats

Gong Qianming, Li Zhi, Wang Ye, Wu Bin, Zhang Zhengyi, and Liang Ji. The effect of high-temperature annealing on the structure and electrical properties of well-aligned carbon nanotubes. United States: N. p., 2007. Web. doi:10.1016/j.materresbull.2006.06.023.
Gong Qianming, Li Zhi, Wang Ye, Wu Bin, Zhang Zhengyi, & Liang Ji. The effect of high-temperature annealing on the structure and electrical properties of well-aligned carbon nanotubes. United States. doi:10.1016/j.materresbull.2006.06.023.
Gong Qianming, Li Zhi, Wang Ye, Wu Bin, Zhang Zhengyi, and Liang Ji. Thu . "The effect of high-temperature annealing on the structure and electrical properties of well-aligned carbon nanotubes". United States. doi:10.1016/j.materresbull.2006.06.023.
@article{osti_21000604,
title = {The effect of high-temperature annealing on the structure and electrical properties of well-aligned carbon nanotubes},
author = {Gong Qianming and Li Zhi and Wang Ye and Wu Bin and Zhang Zhengyi and Liang Ji},
abstractNote = {Systematic work has been performed on the effect of high-temperature annealing on structural defects and impurities of well-aligned carbon nanotubes (ACNTs) in this paper. ACNTs had been prepared by CVD process with ferrocene as catalyst and then the as-grown samples were experienced heat treatment (HT) from 1800 to 3000 deg. C. X-ray diffraction, Raman spectroscopy and electron dispersive spectroscopy (EDS), etc., have been used to analyze the effect of annealing. Results indicate that some impurities can be removed once annealing temperature exceeds vaporization point of corresponding metal or non-metal. Desorption of O should be attributed to reduced active sites of dangling covalent bonds after heat treatment. Specious discrepancy about interlayer spacing resulted from XRD and Raman tests show that although high-temperature heat treatment can remove in-plane defects of carbon nanotubes greatly, interlayer spacing between graphene shells could not be reduced effectively because of the special concentric cylindrical structure of nanotubes. Electrical resistivity of ACNTs block is about three orders higher than that of copper even after HT at 3000 deg. C, and the anisotropy of electrical properties increased once experienced heat treatment at increased temperature.},
doi = {10.1016/j.materresbull.2006.06.023},
journal = {Materials Research Bulletin},
number = 3,
volume = 42,
place = {United States},
year = {Thu Mar 22 00:00:00 EDT 2007},
month = {Thu Mar 22 00:00:00 EDT 2007}
}
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