Abstract: | In order to develop a new strategy to deposit nano-particle sized water oxidation catalyst based on earth abundant element to the photoanode in a photoelectrochemical cell for water splitting, Co_3O_4 as water oxidation catalyst was prepared and subsequently modified by 3-aminopropyltriethoxysilane. The amino functionalized Co_3O_4 catalyst was carefully characterized and then integrated to the ruthenium dye sensitized photoelectrode through fast Schiff base reaction. Cyclic voltammetry experiments in the dark confirmed that the modified Co_3O_4 catalyst was still active toward water oxidation, which could be initiated by oxidation of the ruthenium photosensitizer. Under visible light irradiation, incorporation of the modified Co_3O_4 catalyst resulted in dramatic enhancement of the transient photocurrent density for the photoanode, which was 8 times higher than that of without Co_3O_4 catalyst. |