Zirconium oxide for PEFC cathodes

The electrocatalytic activity of sputtered ZrOx catalyst for the oxygen reduction reaction (ORR) and its solubility in the acidic medium are shown. The saturated solubility of the sputtered ZrOx was 3.23 x 10(-4) g-Zr dm(-3) (0.32 ppm) in 1 mol dm(-3) H2SO4 at 70 degrees C. This shows that ZrOx has high stability in acid medium. The oxygen reduction current of ZrOx was observed below 0.9 V, which indicates a clear catalytic activity of ZrOx for the ORR. The electrocatalytic activity of ZrOx for ORR was affected by the sputtering conditions and was enhanced by Au. This study was an investigation to see if ZrOx might be a substitute for platinum cathodes in polymer electrolyte fuel cells (PEFCs). (c) 2005 The Electrochemical Society.