New Catalysts For PEM Fuel Cell Cathodes
The proton-exchange-membrane (PEM) fuel cell has potential for use in automobiles fueled by air and hydrogen, but new catalysts are required before that hope can be realized for mass production, especially because of the cost of the Pt currently used. As well, Pt has less than ideal kinetics for the oxygen reduction reaction (ORR). The research in this project investigated new non-precious metal catalysts for ORR, and emphasized materials formed by such transition metal catalysts as Co, Fe or Cr in combination with a chalcogen (S or Se). An important part of this research involved fabricating these materials in thin-film form by sputter deposition, and characterizing them before and after undergoing ORR in an electrochemical environment. The program involved a partnership with Dr. Stephen Campbell (Ballard Power Systems), and with UBC colleagues Profs. Dan Bizzotto and Bob Parsons; the group as a whole combined complementary expertise in electrochemistry, surface analysis, materials fabrication and fuel cell science and technology. The reactivities of the thin-film catalysts were compared with those prepared as powders dispersed on carbon supports (prepared both by traditional solution chemistry methods and by magnetron sputtering).