Photoelectrochemical application of mesoporous TiO_2/WO_3 nanohoneycomb prepared by sol-gel method

摘要

A mesoporous TiO_2/WO_3 nanohoneycomb at a molar ratio of 3:1 was prepared by sol-gel method for photoelectrochemical splitting of water. In order to create a highly porous structure, the composite TiO_2/WO_3 with a block copolymer internal template was deposited on the substrate covered with polystyrene (PS) nanospheres. A mesoporous TiO_2/WO_3 composite nanohoneycomb was obtained after removing the PS spheres and copolymer by thermal treatment. It exhibited a lower band gap energy than TiO_2 so that the optical absorption edge was shifted toward the visible light region. It also showed a better photoelectrochemical efficiency of water splitting and higher production of hydrogen due to lower energy gap, higher reactive surface area, and better charge separation efficiency.