Electrochemical and Photoelectrochemical Water Oxidation by Supported Cobalt–Oxo Cubanes

Cobalt–oxo cubane clusters were immobilized on a Nafion film-coated fluorine-doped tin oxide (FTO) electrode and an α-Fe₂O₃ photoanode as surface catalysts for water oxidation. The performance of electrochemical water splitting indicated that these earth-abundant metal complexes retain their homogeneous reactivity on the electrode. Furthermore, efficient visible light-driven water oxidation was realized by coupling a molecular electrocatalyst with an inorganic semiconductor as a noble metal-free photoanode, showing a stability significantly improved with respect to that of the homogeneous system.