Multi-walled carbon nanotube with multivacancy defects: porous structure and Pt decoration.

Abstract

This study reports on the morphological characteristics of multi-walled carbon nanotube with multi-vacancy defects (MWCNT-MD) of carbon atoms and shows the potential of MWCNT-MD as a support for metal deposition by decorating Pt nanoparticles (NPs). Multi-carbon vacancies on MWCNT were introduced by oxidizing cobalt oxide-decorated MWCNT at 250 degrees C for 6 h in air by means of carbon gasification reaction, resulting in holes and thinned walls on MWCNT. It was revealed that creating multivacancy defects led to the increase of specific surface area from 107 to 152 m2/g and pore size in the range of 5-8 nm increased on MWCNT compared with that of pristine MWCNT. 30 wt.% Pt was decorated on MWCNT-MD by impregnation method to investigate the effect of carbon vacancies on the degree of Pt dispersion, and the presence of Pt metal was confirmed by X-ray diffraction. Transmission electron microscopy images clearly displayed that Pt NPs with average particle size of 2.8 nm were evenly dispersed on the defective site of holes and thinned walls. This study is clear evidence showing that defective sites of MWCNT are active and good anchor site for metal decoration.