China-EU Institute for Clean and Renewable Energy, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China.
Engineering Research Center for Functional Ceramics of the Ministry of Education, School of Optical and Electronic Information, Huazhong University of Science and Technolog, Wuhan, 430074, People's Republic of China.
Environ Sci Pollut Res Int. 2019 Jun;26(17):17696-17706. doi: 10.1007/s11356-019-05079-0. Epub 2019 Apr 27.
The development of new technologies for efficient degradation of pollutant has been an increasing demand in the globe due to the serious environmental issues. Herein, we report n-type ZnO/p-type BiFeO composites as highly efficient visible light nanophotocatalysts prepared via a wet chemical solution method. Based on the measurements of OH-related fluorescence (FL) spectra, photoluminescence (PL) spectra, photoelectrochemical I-V curves, and electrochemical impedance spectra (EIS), it is demonstrated that the photo-induced charge carrier (electron-hole pairs) in the as-prepared n-type ZnO/p-type BiFeO composites with proper amount of the coupled ZnO (10% by mass) exhibits high separation compared with the bare BiFeO (BFO) nanoparticles. This is well responsible for the superior visible light photocatalytic performance of the composites for 2,4-dichlorophenol (2,4-DCP) and rhodamine B (RhB) degradation. It is confirmed by means of scavenger test and liquid chromatography-tandem mass spectrometry (LC/MS) analysis of the intermediate products that OH is the pre-dominant oxidant involved in the degradation of 2,4-DCP. A detailed reaction pathway for 2,4-dichlorophenol degradation over the amount-optimized ZnO/BFO composite is proposed mainly based on the LC/MS product ions. This work will provide a feasible route to design and develop BFO-based highly efficient visible light-active photocatalysts for environmental purification and could be extended to other visible light-active semiconductor materials.
由于严重的环境问题，在全球范围内，开发高效降解污染物的新技术的需求日益增长。在此，我们报告了通过湿法化学溶液法制备的高效可见光纳米光催化剂 n 型 ZnO/p 型 BiFeO 复合材料。通过测量 OH 相关荧光（FL）光谱、光致发光（PL）光谱、光电化学 I-V 曲线和电化学阻抗谱（EIS），证明了在具有适量耦合 ZnO（质量比为 10%）的制备的 n 型 ZnO/p 型 BiFeO 复合材料中，光诱导载流子（电子-空穴对）与裸 BiFeO（BFO）纳米粒子相比表现出高分离。这是复合材料在可见光下对 2,4-二氯苯酚（2,4-DCP）和罗丹明 B（RhB）降解具有优异光催化性能的原因。通过猝灭实验和中间产物的液相色谱-串联质谱（LC/MS）分析证实，OH 是参与 2,4-DCP 降解的主要氧化剂。基于 LC/MS 产物离子，提出了一个用于在优化量的 ZnO/BFO 复合材料上降解 2,4-二氯苯酚的详细反应途径。这项工作将为设计和开发基于 BFO 的高效可见光活性光催化剂以进行环境净化提供一条可行的途径，并可扩展到其他可见光活性半导体材料。
