采用一步水热法和原位共沉淀法制备了一种具备可见光响应的双Z型复合光催化剂Ag/AgCl/Bi2WO6/Bi2MoO6,通过扫描电子显微镜、X射线衍射分析仪、X射线光电子能谱仪、紫外-可见漫反射光谱仪表征了复合光催化剂的形貌、结构、组成和吸光性能。以罗丹明B(RhB)为模拟污染物在可见光照射下进行降解以此评价复合光催化剂的性能。结果表明,AgCl、Bi2WO6和Bi2MoO6构建的双Z型异质结具有较高的催化活性,120min内对RhB的降解率高达97.8%。通过在催化剂表面进行光照还原出单质Ag而产生的局部等离子共振效应,增强了复合催化剂对可见光的吸收强度。此外,提出了双Z型Ag/AgCl/Bi2WO6/Bi2MoO6复合光催化剂降解RhB的作用机理。
A double Z-scheme composite photocatalyst Ag/AgCl/Bi2WO6/Bi2MoO6 with visible light response was prepared by one-step hydrothermal method and in-situ coprecipitation method.The morphology,structure,composition and absorbance properties of the composite photocatalyst were characterized by scanning electron microscopy,X-ray diffraction,X-ray photoelectron spectrometer and ultraviolet-visible diffuse reflectance spectrometer.Rhodamine B (RhB) was used as a simulated pollutant to evaluate the performance of the composite photocatalyst by degrading RhB under visible light.The results showed that the double Z-scheme heterojunction constructed by AgCl,Bi2WO6 and Bi2MoO6 had high catalytic activity,and the degradation rate for RhB was as high as 97.8% within 120min.The absorption intensity of visible light of the composition photocatalyst was enhanced by the local plasma resonance effect caused by the light reduction of elemental Ag on the surface of the catalyst.In addition,a possible mechanism of RhB degradation by the double Z-scheme Ag/AgCl/Bi2WO6/Bi2MoO6 photocatalyst was proposed.
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