Three oxidation treatment methods have been adopted to bring oxygen functional groups into the structure of carbon nanotubes (CNTs). The structure and morphology of original and oxidized CNTs have been characterized using Raman, FTIR, XPS, TG, N-2 cryonic adsorption and TEM techniques. The thermal behaviour of various CNTs-containing suspensions in decalin has been measured under microwave irradiation, and correlated with their electrical conductivity. The results show that the oxidation treatments not only introduce the oxygenated groups but also partially damage or even break the graphene layer structure of CNTs. The electrical conductivity of CNTs decreases consequently rendering the thermal behaviour of the oxidized CNTs inferior. The catalytic performance of Pt catalysts supported on the original and the oxidized CNTs has been evaluated in the reaction of hydrogen releasing from decalin under microwave irradiation and compared with that presented using conventional heating. The Pt catalysts supported on the oxidized CNTs performs worse than the Pt/CNT-Original catalyst in terms of average reaction rate and selectivity by taking whatever heating methods. The depressed catalytic activity can be ascribed to the limitation of hydrogen diffusion due to the entrapment of a majority of Pt particles inside the hollow tubes of the oxidized CNTs. The strong coupling effect of CNT suspensions with microwave can induce higher reaction temperatures, which can explain the superior catalytic performance under microwave irradiation than using conventional heating. (C) 2016 Elsevier B.V. All rights reserved.