Zhang Liang, Zhao Chao-Cheng, Gao Xian-Yao, Yan Qing-Yun, Wang Shuai-Jun, Dong Pei, Hou Ya-Lu
College of Chemical Engineering, China University of Petroleum(East China), Qingdao 266580, China.
State Key Laboratory of Petroleum Pollution Control and Treatment, Beijing 102206, China.
Huan Jing Ke Xue. 2019 Jan 8;40(1):281-292. doi: 10.13227/j.hjkx.201806081.
Based on a two-step approach, a flower-like MoS/BiOI composite with a heterojunction has been successfully fabricated. X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS) were used to characterize the prepared MoS/BiOI. The formation mechanism of this heterostructure was investigated. The valence band (VB) and conduction band (CB) of the MoS/BiOI heterojunction have been calculated based on electrochemical characterization, implying the formation of a type I band alignment. The photodegradation of Rhodamine B (RhB) and Cr were used to assess photocatalytic reduction and oxidation activities. The results show that the MoS/BiOI composite structures perform much better than pristine MoS and BiOI. Among the composites with various MoS contents, 2% MoS/BiOI exhibits the best efficiency with respect to the degradation of RhB. After irradiation for 20 minutes, the degradation rate of RhB was 98.82%, which is 1.79 times higher than that using pure BiOI. After irradiation for 80 minutes, the removal of Cr was 97.87%, which is 3.85 times higher than that using pure BiOI. Holes and·O are the main reactive species during the photocatalytic process of RhB degradation; holes play the leading role.
基于两步法，成功制备了具有异质结的花状MoS/BiOI复合材料。采用X射线衍射（XRD）、扫描电子显微镜（SEM）、紫外-可见漫反射光谱（DRS）和X射线光电子能谱（XPS）对制备的MoS/BiOI进行了表征。研究了这种异质结构的形成机理。基于电化学表征计算了MoS/BiOI异质结的价带（VB）和导带（CB），表明形成了I型能带排列。采用罗丹明B（RhB）和Cr的光降解来评估光催化还原和氧化活性。结果表明，MoS/BiOI复合结构的性能比原始的MoS和BiOI好得多。在具有不同MoS含量的复合材料中，2%MoS/BiOI对RhB的降解表现出最佳效率。照射20分钟后，RhB的降解率为98.82%，比使用纯BiOI时高1.79倍。照射80分钟后，Cr的去除率为97.87%，比使用纯BiOI时高3.85倍。空穴和·O是RhB降解光催化过程中的主要活性物种；空穴起主导作用。
