化学刻蚀法制备BiOBr/Bi_(2)O_(2)CO_(3)异质结及其高效脱除Hg^(0)性能  

Preparation of BiOBr/Bi_(2)O_(2)CO_(3) Heterojunction by Chemical Etching and its Efficient Removal of Hg^(0)

作　　者：张景繁 栗敏 张倩倩 张旭 王晨凯 刘艳雯 路好[2] 张安超[2] ZHANG Jingfan;LI Min;ZHANG Qianqian;ZHANG Xu;WANG Chenkai;LIU Yanwen;LU Hao;ZHANG Anchao(China Resources Power Jiaozuo Co.,Ltd.,Jiaozuo 454450,Henan,China;School of Mechanical and Power Engineering,Henan Polytechnic University,Jiaozuo 454003,Henan,China)

机构地区：[1]华润电力焦作有限公司,河南焦作454450 [2]河南理工大学机械与动力工程学院,河南焦作454003

出　　处：《能源研究与管理》2024年第4期98-108,共11页Energy Research and Management

基　　金：国家自然科学基金项目(51676064);河南省自然科学基金项目(232300420082);河南理工大学创新科研团队项目(T2020-3)。

摘　　要：为增强BiOBr对可见光的利用率和提高其光催化活性,采用简单的化学刻蚀法制备出p-n型BiOBr/Bi_(2)O_(2)CO_(3)异质结光催化剂,并研究其在荧光灯下脱除单质汞(Hg^(0))的性能;采用多种表征技术对光催化剂的物理化学结构属性进行分析,阐明复合物表面或界面处电荷分离和转移的过程。结果表明:所制备Bi_(2)O_(2)CO_(3)-3光催化剂的脱汞效率效果高达95%;SO_(2)对Bi_(2)O_(2)CO_(3)-3光催化剂脱汞性能抑制明显,但停止通入SO_(2)后,脱汞性能可以恢复;荧光灯辐照对脱汞效率至关重要;强碱性环境下,过量的OH^(-)与光照产生的空穴(h^(+))反应,会略微影响BiOBr/Bi_(2)O_(2)CO_(3)的汞脱除性能。研究发现BiOBr和Bi_(2)O_(2)CO_(3)异质结的形成会降低光生电子和空穴的复合,增强光催化能力。机制分析表明,在光催化脱汞过程中,·O_(2)^(-)和h^(+)为主要活性物种,·OH未参与反应。To enhance the utilization rate of BiOBr for visible light and improve its photocatalytic activity,p-n type BiOBr/Bi_(2)O_(2)CO_(3) heterojunction photocatalysts were prepared by a simple chemical etching method,and the performance of elemental mercury(Hg^(0))removal under fluorescent lamp(FSL)was carried out.The physical and chemical properties of photocatalysts were analyzed by various characterization techniques to clarify the charge separation and transfer process at the surface or interface of the composites.The results showed that the mercury removal efficiency of the as-prepared Bi_(2)O_(2)CO_(3)-3 photocatalyst could reach as high as 95%.The removal performance of Bi_(2)O_(2)CO_(3)-3 photocatalyst was significantly inhibited by SO_(2), but the removal efficiency could be restored when SO_(2) was stopped. Fluorescent lamp irradiation was very importantfor photocatalytic process. In the strong alkaline environment, the excess OH^(-) would react with the hole (h^(+)) generated byFSL light, which slightly affected the mercury removal efficiency of BiOBr/Bi_(2)O_(2)CO_(3). It was found that the heterojunctionformation between BiOBr and Bi_(2)O_(2)CO_(3) could reduce the recombination of photogenerated electrons and holes, and improvetheir photocatalytic performance. The mechanism analysis exhibited that the·O_(2)^(-) and h+ were the main active species, while·OH was not involved in the photocatalytic Hg^(0) removal process.

关 键 词：湿法光催化 BiOBr/Bi_(2)O_(2)CO_(3) 单质汞脱除 p-n型异质结 

分 类 号：X701[环境科学与工程—环境工程]