Effect of heat treatment on catalytic activity for oxygen reduction reaction of TaOxNy/Ti prepared by electrophoretic deposition

The catalytic activity for the oxygen reduction reaction (ORR) of TaOxNy/Ti, which was prepared by electrophoretic deposition and heat treatment in the temperature range from 700 to 1000 degrees C under flowing N-2 containing 0.1% oxygen, was investigated. The solubility of the TaOxNy powder heat-treated at 800 degrees C was less than 3.3 x 10(-7) mol dm(-3) in 0.1 mol dm(-3) H2SO4 at 50 degrees C under atmospheric conditions. This shows that TaOxNy had a high chemical stability in an acid solution. The catalytic activity for the ORR significantly depended on the heat-treatment temperature, and TaOxNy/Ti heat-treated at 900 degrees C showed the highest activity. (c) 2006 The Electrochemical Society.