Oxygen Electrocatalysis on Some Oxide Pyrochlores

Pyrochlore structure oxides described by the formula , where , , and , have been evaluated for oxygen electrocatalysis. In alkaline electrolyte between room temperature and 110°C, these materials display significantly lower polarizations than any other catalyst for evolution and are among the best for reduction. Rotating ring disk experiments have not detected soluble as an intermediate during reduction. It has been established that reasonable activity maintenance is achievable over relatively long periods (500–1800 hr).