Three dimensional urchin-like ordered hollow TiO2/ZnO nanorods structure as efficient photoelectrochemical anode

Abstract We report a 3D ordered urchin-like hollow TiO 2 /ZnO nanorods structure on transparent FTO substrates that serves as photoanode for efficient photoelectrochemical anode. The ordered urchin-like TiO 2 /ZnO structure is prepared by a combination of colloidal spheres template, atomic layer deposition and hydrothermal growth method. Under simulated sunlight illumination, the CdS sensitized urchin-like TiO 2 /ZnO photoanode generates a photocurrent of 3.6 mA cm −2 at 0 V vs Ag/AgCl, which is higher than that of either 2D TiO 2 /ZnO inverse opals or 1D ZnO nanowire arrays, due to its 3D structural advantages that offers higher surface area for quantum dots loading plus enhanced light scattering ability.