WO3/γ-Bi2MoO6异质结的制备及其光催化性能

采用微波溶剂热法—浸渍法制备了WO₃/γ-Bi₂MoO₆纳米异质结复合可见光催化剂（简称光催化剂）,用XRD、SEM、XPS和UV-Vis分光光度法对其进行了表征。以甲基橙为目标降解物,考察了光催化剂的催化性能。表征结果显示：WO₃分散在γ-Bi₂MoO₆晶体表面,未进入晶格内部;与WO₃和γ-Bi₂MoO₆相比,WO₃/γ-Bi₂MoO₆在紫外和可见光区的吸收强度均有所提高,且对光的吸收发生了明显的红移,禁带宽度变窄;二者形成的p-n型异质结能及时有效地促进光生电子-空穴对的分离,提高催化活性。实验结果表明：WO₃/γ-Bi₂MoO₆的催化活性优于WO₃和γ-Bi₂MoO₆;在甲基橙溶液初始质量浓度为10 mg/L、光催化剂WO₃（1.0%）/γ-Bi₂MoO₆加入量为1 g/L时,反应3 h时甲基橙的降解率最高（达97.48%）,甲基橙溶液中TOC的去除率也最高（为92.0%）。

Preparation of WO3/γ-Bi2MoO6 Heterojunction and Its Photocatalytic Activity

The composite visible-light responsive photocatalyst,WO₃/γ-Bi₂MoO₆ heterojunction,was prepard by microwave solvothermal technique and impregnation method,and characterized by XRD,SEM,XPS and UV-Vis spectrophotometry. Its photocatalytic activity was investigated using methyl orange as target degradation material. The characterization results show that：WO₃ disperses on the surface of γ-Bi₂MoO₆ crystal,instead of into the crystal lattice;Compared with WO₃ and γ-Bi₂MoO₆,both of UV- and Vis- absorption intensities of WO₃/γ-Bi₂MoO₆ are improved,the spectrum migrates toward red and the band gap is narrowed;The p-n type heterojunction formed by WO₃ and γ-Bi₂MoO₆ can effectively promote the separation of photo-induced electron-hole pair and increase the visible-light photocatalytic activity. The experimental results show that：The photocatalytic activity of WO₃/γ-Bi₂MoO₆ is much better than those of WO₃ and γ-Bi₂MoO₆;When the initial mass concentration of the methyl orange solution is 10 mg/L,the dosage of WO₃（1.0%）/γ-Bi₂MoO₆ is 1 g/L and the reaction time is 3 h,the degradation rates of methyl orange and TOC are the highest （97.48% and 92.0% respectively）.