有机酸介导合成WO3/g-C3N4及其光催化性能

采用水热法制备了WO3/g-C3N4复合物,并探讨了草酸、柠檬酸、乙酸和水杨酸对复合物结构、形貌及催化活性的影响。结果表明,复合物中棒状WO3分布在片层状的g-C3N4上,二者结合紧密形成异质结构。以1 mol/L草酸为介导剂制备的WO3/g-C3N4的光催化活性最佳,当WO3和g-C3N4质量比为1∶1时,可见光下反应210 min,对罗丹明B的降解率达97.46%。自由基捕获实验表明,光催化反应活性基团排序为·O2->h+>·OH。经推测,光催化降解机制符合Z型机制。

Synthesis of WO3/g-C3N4 mediated by organic acids and its photocatalytic activity study

WO3/g-C3N4 composites were prepared by employing the hydrothermal method.The effects of oxalic acid,citric acid,acetic acid and salicylic acid on the structure,morphology and catalytic activity of the composites were discussed,respectively.The results showed that the rod-like WO3 in the composite was distributed on the sheet-like g-C3N4,so that the close contact between them was beneficial to forming a heterostructure.The photocatalytic activity of WO3/g-C3N4 prepared with the oxalic acid(1 mol/L)as the mediator was the best.When the mass ratio of WO3 and g-C3N4 was 1∶1,the removal rate of Rhodamine B(RhB)reached up to 97.46%under visible light for 210 min.Free radical trapping experiments showed that the order of active group in photocatalytic reaction process was·O2->h+>·OH.Furthermore,the results indicated that the mechanism of photocatalytic degradation confirmed to the Z-scheme mechanism.