Direct formation of a water oxidation catalyst from thin-film cobalt

A cobalt-based water oxidation catalyst may be grown from sputter-deposited thin films (800 nm thick) of cobalt metal on a non-conductive glass substrate. Chemical composition and function of the catalyst prepared in this manner are similar to that for catalyst films prepared by electrodeposition of the catalyst from aqueous solutions of Co(2+) salts. The method permits water oxidation catalysis to be established from protective barrier layers on materials that otherwise experience corrosion under the aqueous oxidative conditions.