Photocatalytic water splitting for hydrogen generation driven by tetragonal, trigonal, hexagonal and cubic LiCoO and visible light.

The photocatalytic properties of LiCoO are not explored up to date although its cubic and trigonal structures are explored experimentally. Here, we investigate the feasibility of photocatalytic hydrogen production from water splitting driven by the tetragonal, trigonal, hexagonal and cubic LiCoO with the irradiation of the visible light. The band structure, density of state, optical absorption and mobility are calculated by the first-principles density functional theory. The results show that the band edges of all the four structures of LiCoO match to the conditions of the redox potentials of water splitting reaction and the enhanced optical absorption in the visible light range is observed. The obvious difference between the mobilities of the hole and electron are identified, especially for the cubic LiCoO. All the obtained results suggest that the considered structures of LiCoO are promising candidates for the photocatalytic water splitting to produce hydrogen with the irradiation of the visible light.