PdCu纳米合金电催化还原氟苯尼考的研究  

Electrocatalytic reduction of florfenicol over PdCu nanoparticles catalysts

作　　者：杜琳[1] 楼耀尹 王晓君[2] 陈少华[2] DU Lin;LOU Yaoyin;WANG Xiaojun;CHEN Shaohua(College of Environment&Safety Engineering,Fuzhou University,Fuzhou 350108;CAS Key Laboratory of Urban Pollutant Conversion,Institute of Urban Environment,Chinese Academy of Sciences,Xiamen 361021)

机构地区：[1]福州大学环境与安全工程学院,福州350108 [2]中国科学院城市环境研究所,城市污染物转化重点实验室,厦门361021

出　　处：《环境科学学报》2024年第9期261-270,共10页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.22002131)。

摘　　要：如何构筑高性能的电催化剂是提高卤代有机污染物电催化还原去除的关键.本研究通过化学共还原的方法制备出钯铜(PdCu)纳米合金催化剂,通过扫描电子显微镜(SEM)、高分辨率透射电子显微镜(HRTEM)、能量色散X射线光谱(EDX)、X射线衍射(XRD)、X射线光电子能谱(XPS)、线性扫描伏安法(LSV)和电化学阻抗谱(EIS)等方法对其微观结构和电化学性能进行表征,并探究PdCu纳米合金催化剂对抗生素氟苯尼考(Florfenicol,FLO)电催化还原的降解机理.实验结果表明,所制备的PdCu纳米合金催化剂中Pd、Cu纳米颗粒分布均匀,具有优异的电化学还原性能和动力学性能以及快速的电子转移速率.PdCu纳米合金催化剂在-1.3 V vs.Hg/Hg_(2)SO_(4)下,120 min内对FLO的去除率高达97.5%,远高于纯Pd(82.9%)、纯Cu(67.4%)金属纳米颗粒催化剂的去除率,中性pH更有利于FLO的降解.叔丁醇淬灭实验表明,吸附态原子氢在电催化还原去除FLO过程中起重要作用.使用液质联用仪(LC-MS/MS)对FLO降解后的产物进行半定量分析表明,在PdCu纳米合金催化剂上FLO的电催化还原是一个逐步脱卤的过程,在实现完全脱氯后再进行脱氟.本研究为电催化高效还原卤代有机污染物提供了一种具有应用潜力的催化剂方案.Rational design of electrocatalysts with improved catalytic properties is critical to achieving high removal efficiency of halogenated organic pollutants by electrocatalytic reduction.In this study,PdCu nanoalloy catalysts were prepared by using chemical co-reduction.The microstructures and electrochemical properties of the catalysts were characterized by scanning electron microscope(SEM),high-resolution transmission electron microscopy(HRTEM),energy dispersive X-ray spectroscopy(EDX),X-ray diffractometer(XRD),X-ray photoelectron spectroscopy(XPS)analysis,linear sweep voltammetry(LSV)and electrochemical impedance spectra(EIS).Subsequently,the degradation mechanism of florfenicol(FLO,one of typical halogenated antibiotics)by PdCu nanoalloy catalysts in electrocatalytic reduction was investigated.The results showed that Pd and Cu were uniformly distributed in nanoparticles.The PdCu catalysts have excellent electrocatalytic capacity,kinetic performances,and electron transfer rate.The removal efficiency of FLO was as high as 97.5%within 120 min under the voltage of-1.3 V vs.Hg/Hg_(2)SO_(4),much higher than that of metallic nanoparticle catalysts Pd(82.9%)and Cu(67.4%).Neutral pH benefits FLO degradation.Quenching experiments showed that the adsorbed atomic hydrogen played an important role in FLO removal.Furthermore,results from mechanism study using liquid-mass spectrometry(LC-MS/MS)revealed that the electrocatalytic reduction of FLO over PdCu nano-alloy catalysts was achieved by stepwise dehalogenation,that was,dechlorination occurred first followed by defluorination.This study provides a promising catalyst scheme for efficient reduction of halogenated organic pollutants through electrocatalytic reactions.

关 键 词：氟苯尼考 PdCu纳米合金催化剂 电催化还原 原子氢 

分 类 号：X703[环境科学与工程—环境工程]