Noble Metal and Mn₃O₄ Supported Carbon Nanotubes: Enhanced Catalysts for Ethanol Electrooxidation

摘要

The carbon nanotubes (CNT) were modified by Mn3O4 before deposition of metal catalysts (e.g. Pt andPd) by improved polyol method. Crystallinity, morphology and composition of the synthesizedelectrocatalysts were characterized by Fourier transform infrared (FT-IR) spectroscopy, x-raydiffraction (XRD), transmission electron microscopy (TEM) and energy dispersive x-ray spectroscopy(EDS). It was found that the Mn3O4 nanoparticles are dispersed and covered the CNT surface. Thevarious atomic ratios of 10 wt% PtxPdy nanoparticles are also uniformly dispersed on Mn3O4-CNTwith the particle size of 1 - 4 nm. Their electrocatalytic performances in ethanol oxidation wereinvestigated by cyclic voltammetry (CV) and Chronoamperometry (CA). The prepared catalystshowed enhanced catalytic activity and more stability than the commercially available PtRu/VulcanXC-72 catalyst. It is proposed that additions of metal oxides and noble metal could develop active sitesfor ethanol oxidation, which their catalytic performances were improved. These results imply that theprepared various atomic ratios PtxPdy/Mn3O4-CNT nanocomposite could be a promising electrocatalystto enhance performance of direct ethanol fuel cell applications.