Zirconium Oxide-Based Compound as New Cathode Without Platinum Group Metals for PEFC

Partially oxidized zirconium carbonitride (Zr-CNO) powders were evaluated as a nonprecious metal cathode for polymer electrolyte fuel cells (PEFCs). Zr-CNO powders were prepared from zirconium carbonitrides with heat-treatment under containing 2% and 0.25% gas at . Voltammetry was performed to evaluate the catalytic activity for oxygen reduction reaction (ORR) under nitrogen and oxygen in at . Although the onset potential of the ORR for untreated was 0.55 V vs a reversible hydrogen electrode (RHE), the onset potential of the appropriate oxidized Zr-CNO reached 0.97 V vs RHE. X-ray diffraction and X-ray photoelectron spectroscopy data suggested that the surface of Zr-CNO was oxidized to , and remained in the inner part of the Zr-CNO particles.