Surface and electrochemical investigations of a fullerene soot

A study of the surface and electrochemical properties of a fullerene soot submitted to several types of heat treatment was conducted. The surface characteristics were investigated for the chemical properties using FTIR and for the specific area using BET. The electrochemical properties were investigated employing the thin porous coating electrode technique, in the presence and absence of dispersed platinum particles. In each case the responses were compared taking as reference the Vulcan XC-72 carbon powder, frequently considered as electrochemical substrates for dispersed electrocatalysts. It is observed that the fullerene soot presents a higher level of oxygenated surface groups, lower conductivity, but larger surface area and high charge storage capacity than the Vulcan XC-72 and Shawinigan carbons. Values of active surface area of dispersed platinum particles close to that on Vulcan are obtained when fullerene soot is employed as catalyst substrate. (C) 1999 Elsevier Science Ltd. All rights reserved.44203565357

Investigation of enhanced CO tolerance in proton exchange membrane fuel cells by carbon supported PtMo alloy catalyst

We report a two- to threefold enhancement of CO tolerance in a proton exchange membrane (PEM) fuel cell, exhibited by carbon supported nanocrystalline PtMo/C as compared to the current state of the art PtRu/C electrocatalysts. The bulk of these nanocrystals were comprised of Pt alloyed with Mo in the ratio 8.7: 1.3 as shown by both X-ray diffraction and in situ extended X-ray absorption fine structure measurements. Rotating disk electrode measurements and cyclic voltammetry in a PEM fuel cell indicate the onset of CO oxidation at potentials as low as 0.1 V. Further, the oxidation of CO exhibits two distinct peaks, indicating redox behavior involving oxyhydroxides of Mo. This is supported by in situ X-ray absorption near edge structure measurements at the Mo K edge