Electron and proton transport in gas diffusion electrodes containing electronically conductive proton-exchange polymers

A novel supported catalyst has been prepared by the chemical deposition of Pt particles on a polypyrrole \ polystyrenesulphonate (PPY \ PSS) composite . The chemically prepared polymer particles were designed to provide a poro us, proton and electron conducting catalyst support for use in fuel cells. Transmission electron microscopy, conductivity measurements, impedance spec troscopy, and cyclic voltammetry confirm that these properties have been ac hieved. The chemically prepared PPY \ PSS composite exhibits very high prot on conductivities that are several orders of magnitude higher than for elec trochemically prepared films. Currents of 0.1 A cm(-2) have been observed f or oxygen reduction in proton exchange membrane (PEM) fuel cell type gas di ffusion electrodes. (C) 1998 Elsevier Science S.A. All rights reserved.