Enhanced photocatalytic ammonia oxidation over WO@TiO heterostructures by constructing an interfacial electric field.

WO nanorods and xWO@TiO (WO/TiO mass ratio (x) = 1-5) photocatalysts were synthesized using the hydrothermal and sol-gel methods, respectively. The photocatalytic activities of xWO@TiO for NH oxidation first increased and then decreased with a rise in TiO content. Among them, the heterostructured 3WO@TiO photocatalyst showed the highest NH conversion (58 %) under the simulated sunlight irradiation, which was about two times higher than those of WO and TiO.