Recent advances in photocatalytic water splitting reactions, especially under visible light irradiation, are reviewed here. In line with such work,the development of various unique photocatalysts including cation or anion-doped metal oxides or metal oxynitride has been introduced. Specialattention is focused on the preparation of visible light-responsive TiO2 thin films by a RF-magnetron sputtering method and their applications forthe separate evolution of H2 and O2 from water under visible or solar light irradiation.