Cobalt selenide: a versatile cocatalyst for photocatalytic water oxidation with visible light

Cobalt selenide has been developed as an effective cocatalyst to decorate visible light photocatalysts, including WO3, BiVO4 and g-C3N4, establishing intense surface contact with substrates for the photocatalytic water oxidation reaction. Compared with CoOx and CoSx, CoSe2 is superior for improving the photocatalytic water oxidation activity due to the lower anionic electronegativity, which leads to dense adhesion and enables fast interfacial charge transfer for the water oxidation reaction.