Title

Huge volume expansion and structural transformation of carbon nanotube aligned arrays during electrical breakdown in vacuum

Authors

Authors

S. Shekhar; H. Heinrich;S. I. Khondaker

Comments

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Abbreviated Journal Title

Carbon

Keywords

ENERGY-LOSS SPECTROSCOPY; THIN-FILM TRANSISTORS; GOLD NANOPARTICLES; QUANTUM WIRES; SINGLE; ELECTRONICS; DENSITY; FABRICATION; SCALE; FLEXIBILITY; Chemistry, Physical; Materials Science, Multidisciplinary

Abstract

We observed a huge volume expansion of aligned single walled carbon nanotube (SWCNT) arrays accompanied by structural transformation during electrical breakdown in vacuum. The SWCNT arrays were assembled between prefabricated palladium source and drain electrodes of 2 mu m separation on a silicon/silicon dioxide substrate by dielectrophoresis. At high electrical field, the SWCNT arrays erupt into a large mushroom-like structure. Systematic studies with controlled electrical bias show that above a certain field the SWCNTs swell and transform to nanoparticles and flower-like structures with a small volume increase. Further increases in electrical bias and repeated sweeping results in their transformation into amorphous carbon as determined from scanning electron microscopy and transmission electron microscopy (TEM). Cross-sectional studies using a focused ion beam and TEM show the height of a 2-3 nm SWCNT array increased to about 1 mu m with a volume increase of similar to 400 times. Electron energy loss spectroscopy reveals that graphitic sp(2) networks of SWCNT are transformed predominantly to sp(3). The current-voltage measurements also show an increase in the resistance of the transformed structure. (C) 2011 Elsevier Ltd. All rights reserved.

Journal Title

Carbon

Volume

50

Issue/Number

4

Publication Date

1-1-2012

Document Type

Article

Language

English

First Page

1635

Last Page

1643

WOS Identifier

WOS:000301007800021

ISSN

0008-6223

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