BiOCl/In_(2)S_(3)复合可见光催化剂制备及性能

Preparation and Visible-Light Photocatalytic Performance of BiOCl/In_(2)S_(3) Composite

氯氧化铋(BiOCl)较大的禁带宽度使得其只能对紫外光产生响应,严重制约了其进一步光催化应用。为实现BiOCl对可见光的利用,以In_(2)S_(3)为可见光光敏剂,并基于高效实用的机械研磨手段构建BiOCl/In_(2)S_(3)复合可见光催化剂。通过扫描电镜、X射线能谱、X射线衍射、红外光谱和紫外-可见漫反射光谱等方法对催化剂的形貌和结构进行表征。选择盐酸四环素(TC)可见光催化降解为评价模型,系统研究了BiOCl/In_(2)S_(3)复合比例对光催化活性的影响。结果表明,两者复合比例为1∶1时具有最佳的光催化活性,在可见光照射下对TC的降解效率高达91.4%,且经3次循环后降解效率仍保持在87.3%。机理研究表明,In_(2)S_(3)被可见光激发产生电子注入BiOCl的导带,能有效提升载流子的分离效率,而h^(+)和·O_(2)^(-)是光降解过程中的主要活性物质。该项研究工作充分表明了In_(2)S_(3)对BiOCl的高效光敏活性,展示了物理复合法在新型高效可见光催化体系构建中的重要意义。

Due to the large band gap and poor visible light absorption,the application of BiOCl in the field of visible-light photocatalysis is severely restricted.In order to construct a visible-light photocatalysis system based on BiOCl,we chose In_(2)S_(3)as the visible light photosensitizer to get a new visible-light catalyst BiOCl/In_(2)S_(3)by a simple mechanical grinding method.The morphology and structure of BiOCl/In_(2)S_(3)composite were investigated by SEM,EDS,XRD,FT-IR and UV-Vis DRS.The visible light degradation of tetracycline hydrochloride(TC)was studied by adjusting the ratio of the two components of BiOCl/In_(2)S_(3).The results showed that the degradation efficiency of TC under visible-light irradiation is as high as 91.4%when the ratio of BiOCl/In_(2)S_(3)is 1∶1,and still retains 87.3%after three cycles.Mechanistic studies revealed that electrons excited from In_(2)S_(3)under visible-light irradiation are injected into the conduction band of BiOCl,which can effectively improve the separation efficiency of carriers.As suggested by the results of control experiments,combined with the corresponding redox potential of possible oxidative species,h^(+)and·O_(2)^(-)are the main active species during the photodegradation process.This work demonstrates a facile and promising approach for designing simple,low cost and efficient heterostructure photocatalysts that can be applicable for energy and environmental applications.