Bi2MoO6/g-C3N4Z型异质结的合成及其光催化性能的研究

Synthesis and Photocatalytic Activity of Bi2MoO6/g-C3N4 Z-Scheme Heterojunction

本研究制备了Bi2MoO6/g-C3N4 Z型异质结光催化剂。通过XRD和紫外-可见漫反射光谱表征来测试样品的晶体结构和光吸收性能等性质。结果表明:掺杂Bi2MoO6形成异质结后,g-C3N4的禁带宽度变窄,增强了光催化活性。以罗丹明B为目标污染物,在可见光下研究了pH对Bi2MoO6/g-C3N4的光催化降解性能的影响,研究显示Bi2MoO6/g-C3N4光催化性能优于g-C3N4,在光照1 h内基本可将污染物100%完全降解。最后通过捕获实验验证在光催化过程中起主要作用的是O-2·自由基,并推测出可能的光催化机理。

In this study,Bi2MoO6/g-C3N4 Z-scheme heterojunction photocatalyst was prepared and characterized by XRD and ultraviolet-visible diffuse reflectance spectroscopy.The crystal structure and light absorption properties of the catalyst were tested.The results show that by doping Bi2MoO6 to form heterojunction,the band gap of g-C3N4 was narrowed and the photocatalytic activity was enhanced.By taking Rhodamine B(RhB)as the target pollutant,the effects of pH on photocatalytic degradation of RhB over Bi2MoO6/g-C3N4 were discussed,which indicates that the degradation efficiency was significantly higher than that over g-C3N4 and the pollutant was completely degraded within 1 h of illumination.Finally,trapping experiment was conducted to identify the main active factor as O-2·free radicals in the photocatalytic process,and the possible photocatalytic degradation mechanism was deduced.