Transition Metal Oxide Based Materials for Cathode of Polymer Electrolyte Fuel Cells

Group 4 and 5 metal oxide-based compounds might be candidates for new cathode materials of polymer electrolyte fuel cells, if they have high catalytic activity for oxygen reduction. These materials are stable in acidic and oxidative atmosphere. Among these materials, partially oxidized Ta carbonitride (Ta-CNO) and Zr carbonitride (Zr-CNO) had high catalytic activity for the ORR. Their onset potentials were almost catching Pt/C. The cost of raw material for Ta oxide or Zr oxide is far below the present Pt/C cathode. A significant cost reduction of PEFCs might be possible using these materials.