Oxygen evolution and reduction on iridium oxide compounds

The electrochemical properties of twelve iridium oxide compounds (including pyrochlores, perovskites, fluorites and compounds of another structure) were examined with respect to the oxygen-evolution and the oxygen-reduction reactions. Steady-state current-potential curves were measured in 45% KOII. In addition, the kinetic properties and the electrical conductivity of four iridium oxide pyrochlores were investigated. All twelve compounds have a moderate to high catalytic activity for the oxygen-evolution reaction, and a somewhat lower activity for the oxygen-reduction reaction. Pb2(PbxIr2–x)O7–y and Nd3IrO7 showed the highest activity towards both reactions.