Sarkar, Soumya and Das, Probal Kumar and Bysakh, Sandip (2011) Effect of heat treatment on morphology and thermal decomposition kinetics of multiwalled carbon nanotubes. Materials Chemistry and Physics, 125 (1-2). pp. 161-167. ISSN 0254-0584

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Abstract

High temperature treatment in inert atmosphere proved to be an effective way to improve high temperature stability of MWNTs in ambient condition. TEM analysis of heat-treated MWNTs confirmed successful removal of impurities and formation of ordered graphene layers and internal bamboo structure. TG-DTG curves indicated that decomposition range and rate of as-received MWNTs were narrow and notably higher, respectively, than heat-treated MWNTs mainly due to presence of impurities like metal nanoparticles in the former. Non-isothermal kinetic analysis revealed that the rate determining mechanism for as-received MWNTs was random nucleation and growth of active species. However, for heat-treated MWNTs, rate controlling mechanism was chemical reaction. Higher activation energies (similar to 203 kJ molt and 280 kJ mol(-1)) and reaction orders (3 and 4) of MWNTs heat-treated at 1200 degrees C and 1800 degrees C in inert, respectively, indicated delayed thermal decomposition than as-received MWNTs (E(a) approximate to 178 kJ mol(-1); n =1) even in oxidative atmosphere. (C) 2010 Elsevier B.V. All rights reserved.

Item Type:	Article
Uncontrolled Keywords:	Heat treatment; Electron microscopy; TGA
Subjects:	Physical Properties
Divisions:	Non-Oxide Ceramics & Composites
Depositing User:	Bidhan Chaudhuri
Date Deposited:	18 Jan 2012 06:40
Last Modified:	06 Jun 2012 05:38
URI:	http://cgcri.csircentral.net/id/eprint/347

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