Ag/Ag_(2)O/g-C_(3)N_(4) /BiVO_(4) 复合光催化体系降解盐酸四环素机理研究  

Mechanism Study on Degradation of Tetracycline Hydrochloride by Ag/Ag_(2)O/g-C_(3)N_(4)/BiVO_(4)Composite Photocatalytic System

作　　者：许洋 蒲生彦[1,2] 季雯雯[1,2] 杨曾 XU Yang;PU Shengyan;JI Wenwen;YANG Zeng(State Key Laboratory of Geohazard Prevention and Geoenvironmental Protection,Chengdu University of Technology,Chengdu 610059,China;State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil&Water Pollution,School of Ecological and Environmental Sciences,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学,地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]成都理工大学生态环境学院,国家环境保护水土污染协同控制与联合修复重点实验室,四川成都610059

出　　处：《环境科学研究》2021年第12期2841-2849,共9页Research of Environmental Sciences

基　　金：国家重点研发计划项目(No.2020YFC1808300);国家自然科学基金项目(No.42077185)。

摘　　要：为提高钒酸铋(BiVO_(4))对盐酸四环素(TC-HCl)在水溶液中的降解效率,以银基材料(Ag/Ag_(2)O)和石墨相氮化碳(g-C_(3)N_(4))共同改性BiVO_(4),通过水热法、煅烧法、湿浸渍法、沉淀和热分解法分步制备了Ag/Ag_(2)O/g-C_(3)N_(4)/BiVO_(4)四元复合材料;采用X-射线衍射(XRD)、扫描电子显微镜(SEM)、X-射线光电子能谱(XPS)及紫外-可见漫反射光谱法(UV-vis DRS)等方法对复合材料的形貌结构、元素分布及光学性质进行了表征.结果表明:①沉积了Ag/Ag_(2)O粒子后,复合材料对TC-HCl的吸附能力显著提高.②纳米Ag粒子的表面等离子体共振效应(SPR)以及g-C_(3)N_(4)的协同作用拓宽了光响应范围,表现出更好的光催化性能.③相较于BiVO_(4)、g-C_(3)N_(4)及g-C_(3)N_(4)/BiVO_(4),该复合材料对TC-HCl的降解效果最佳,降解率可达89.19%,且经过4次循环使用后仍能保持74.8%的降解率.④UV-vis及XPS分析证明,该复合材料的可见光响应拓展至548 nm,可吸收更多可见光.⑤体系自由基捕获试验证明,·O_(2)^(-)和h+在光催化降解TC-HCl过程中发挥主要作用,且h+的作用大于·O_(2)^(-).研究显示,Ag/Ag_(2)O/g-C_(3)N_(4)/BiVO_(4)是一种高效稳定的复合光催化剂,其在处理TC-HCl抗生素废水方面具有潜在的应用前景.In order to improve the degradation efficiency of bismuth vanadate(BiVO_(4))on tetracycline hydrochloride(TC-HCl)in aqueous solution,silver-based material(Ag/Ag_(2)O)and graphitic phase carbon nitride(g-C_(3)N_(4))were used to co-modify BiVO_(4),and the Ag/Ag_(2)O/g-C_(3)N_(4)/BiVO_(4)quaternary composites were constructed by hydrothermal,calcination,wet impregnation,precipitation and thermal decomposition methods in a stepwise manner.The composites were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and Ultraviolet-visible diffuse reflectance spectrometry(UV-vis DRS)for their morphological structure,elemental distribution and optical properties.The experimental results showed that:(1)The deposition of Ag/Ag_(2)O particles significantly increased the adsorption capacity of the material for TC-HCl.(2)The surface plasmon resonance effect(SPR)of Ag nanoparticles and the synergistic effect of g-C_(3)N_(4)broadened the photoresponse range and improved the photocatalytic performance.(3)Compared with BiVO_(4),g-C_(3)N_(4)and g-C_(3)N_(4)/BiVO_(4),the composite had the best degradation effect on TC-HCl,with the degradation rate up to 89.19%,and the degradation efficiency was still 74.8%after four cycles.(4)UV-vis and XPS analysis determined that the visible light response of the composite extended to 548 nm and could absorb more visible light.(5)The system radical trapping test demonstrated that·O_(2)^(-)and h+played a major role in the photocatalytic degradation of TC-HCl,and the role of h+was greater than that of·O_(2)^(-).The above results show that Ag/Ag_(2)O/g-C_(3)N_(4)/BiVO_(4)is an efficient and stable composite photocatalyst with potential application in the treatment of TC-HCl antibiotic wastewater.

关 键 词：光催化 石墨相氮化碳(g-C_(3)N_(4)) 氧化银 钒酸铋(BiVO_(4)) 

分 类 号：X142[环境科学与工程—环境科学]