WO3/g-C3N4复合光催化剂制备及其可见光催化性能

将自制层状石墨相氮化碳(g-C₃N₄)和WO₃纳米片均匀混合，经煅烧制备WO₃/g-C₃N₄复合半导体。利用XRD、SEM、TEM、UV-Vis DRS和PL对其进行表征。结果表明，g-C₃N₄呈现类石墨烯状片层结构，WO₃为纳米片状结构，且分散在g-C₃N₄表面；与WO₃复合后，UV-Vis吸收边发生了红移，拓宽了g-C₃N₄对可见光的响应。以罗丹明B(RhB)为模拟污染物，考察WO₃/g-C₃N₄的光催化降解性能。WO₃/g-C₃N₄质量比为1∶5时，表现出最佳的光催化活性，可见光照60 min后，RhB降解率可达到94.9%。光催化剂具有良好的稳定性，重复使用6次后，RhB的降解率依然达到88.9%。光催化机制研究表明，超氧自由基(·O₂?)是光催化降解RhB的主要活性物种。 

Preparation and visible light catalytic performance of WO3/g-C3N4 composite photocatalyst

The WO₃/graphite phase carbon nitride (g-C₃N₄) composites were prepared by mixing self-made layered g-C₃N₄ with WO₃ nanoplates and afterward calcination process, and were characterized by XRD, SEM, TEM, UV-Vis DRS and PL. The results show that g-C₃N₄ presents graphene-like layered structure, and WO₃ indicates nanoplate structure, and scatters on the surfaces of g-C₃N₄. After compounding with WO₃, the absorption edge of UV-Vis spectrum shifts to red, which widens the response of g-C₃N₄ to visible light. The photocatalytic degradation properties of WO₃/g-C₃N₄ were examined using rodamine B (RhB) as a simulated pollutant. When the mass ratio of WO₃/g-C₃N₄ is 1∶5, the best photocatalytic activity is obtained. After 60 min of visible light irradiation, the degradation rate of RhB can reach 94.9%. The photocatalyst shows good stability, as the photodegradation rate of RhB reaches 88.9% after repeated use of the same photocatalyst for 6 times. The study of photocatalytic mechanism shows that superoxide radical (·O₂?) is the main active species for photocatalytic degradation of RhB.