Construction of Urchin-Like ZnO/TiO2 Direct Z-Scheme System to Improve Charge Separation

The Z-scheme system urchin-like ZnO/TiO2 composite superstructure material was successfully prepared via a facile hydrothermal method for the first time. SEM showed that the amount of ammonia can affect the morphology of ZnO. By controlled the addition amount of Ti(SO4)(2), reaction time and temperature, the photocatalytic activity of urchin-like ZnO/TiO2(UZT-4(10.4-150-12)) composite was the highest. The photocatalytic degradation rate of rhodamine B was 95.5%, and the rate constant was 0.0141 min(-1), which was 3.59 times than urchin-like ZnO. XPS measurements confirmed that there is a Z-scheme heterojunction between urchin-like ZnO and TiO2. The improvement of photocatalytic degradation RhB activity should be attributed to a direct Z-scheme system, which not only can increase the separation efficiency of photogenerated electron-hole pairs but also possesses excellent oxidation and reduction ability for high photocatalytic performances.