花状CoMOF中间层修饰钯/泡沫镍电极对三氯乙酸脱氯研究  

Dechlorination of trichloroacetic acid by palladium/nickel foam electrode with a flower-shape CoMOF interlayer modification

作　　者：杨玉海 王方园 蒋纪华 谢欢庆 张彬 庞思婕 裘建平 YANG Yuhai;WANG Fangyuan;JIANG Jihua;XIE Huanqing;ZHANG Bin;PANG Sijie;QIU Jianping(College of Geography and Environmental Sciences,College of Xingzhi,Zhejiang Normal University,Jinhua 321004;Jinhua Xinnuoda Environmental Technology&Service Co.,Ltd,Jinhua 321100)

机构地区：[1]浙江师范大学,行知学院,地理与环境科学学院,金华321004 [2]金华信诺达环境技术服务有限公司,金华321100

出　　处：《环境科学学报》2024年第4期11-21,共11页Acta Scientiae Circumstantiae

基　　金：金华市科技局基金项目(No.2022-3-141);高等学校国内访问学者教师专业发展项目(No.FX2022071)。

摘　　要：针对常规污染控制技术难以去除饮用水中三氯乙酸(Trichloroacetic acid,TCAA)的问题,制备了花状CoMOF中间层修饰钯/泡沫镍电极(Pd/CoMOF/RNF),采用SEM、TEM、XRD、XPS等方法对其进行表征分析,探究了Pd/CoMOF/RNF电极对TCAA的还原脱氯影响因素和实际潜在应用及脱氯强化机制.结果表明:所制备电极具有中空微米花结构,Pd纳米颗粒均匀分布在CoMOF纳米片上;当阴极电位为-1.0 V、TCAA初始浓度为1 mg·L^(-1)、初始pH值为5.5时,反应90 min后,TCAA降解效率达到最高98.2%,且经过5次循环实验后,TCAA脱氯效率基本不变,具有较好的稳定性;氯乙酸(Chloroacetic acid,CAAs)在60 min后就可降至60μg·L^(-1)以下;结合电化学测试、电子自旋共振谱(Electron spin resonance,ESR)测试和密度泛函理论(Density functional theory,DFT)计算,花状CoMOF中间层的引入增加了电极活性面积,提供更多的活性位点,同时促进电子迁移速率,产生更多具有更强吸附能力H*_(ads),从而有效增强脱氯效率.因此利用Pd/CoMOF/RNF电极电催化还原降解TCAA具有很大的应用潜力.Trichloroacetic acid(TCAA)is a challenging pollutant in drinking water,requiring effective control strategies.In this study,a Pd/CoMOF/RNF electrode with a flower-like CoMOF intermediate layer modification was prepared and characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).Subsequently,the influential factors,enhanced reaction mechanism,and practical viability of TCAA catalytic reductive dechlorination were investigated.Results revealed a meticulously crafted hollow micrometer-sized flower structure with uniformly distributed Pd nanoparticles on the CoMOF nanosheets.Remarkably,98.2%of TCAA was successfully removed within 90 mins under optimized conditions(electrode potential of-1.0 V,initial TCAA concentration of 1mg·L^(-1),and initial pH of 5.5).Moreover,the excellent stability of the Pd/CoMOF/RNF cathode was confirmed through five consecutive cycle tests.Following a 60-minute reaction period,the chloroacetic acids(CCAs)concentration was reduced to below 60μg·L^(-1).Meanwhile,the investigation into the electrode′s performance was complemented by a comprehensive analysis combining electrochemical characterization,electron spin resonance(ESR)spectroscopy,and density functional theory(DFT)calculations,which unveiled that the introduction of flower-like CoMOF interlayer increased the active surface area of the electrode,provided abundant active sites,enhanced electron transfer rates,and produced the generation of H~*_(ads)with stronger adsorption capacity,thereby effectively enhancing the dechlorination efficiency.In conclusion,the Pd/CoMOF/RNF electrode holds significant potential for the electrocatalytic reduction of TCAA,presenting a promising solution for practical applications.

关 键 词：电催化加氢脱氯 三氯乙酸 花状CoMOF Pd/CoMOF/RNF电极 

分 类 号：X703[环境科学与工程—环境工程]