铁氮共掺杂碳材料改性磷酸银复合光催化剂对四环素的催化降解性能与机制  

Performance and mechanisms of silver phosphate photocatalysts modified by iron and nitrogen Co-doped carbon material for photocatalytic removal of tetracycline

作　　者：童设华 聂金林 林燕 杨春平[1,2] TONG Shehua;NIE Jinlin;LIN Yan;YANG Chunping(College of Environmental Science and Engineering,Hunan University,Changsha 410082;School of Environmental Science and Engineering,Guangdong University of Petrochemical Technology,Maoming 525000)

机构地区：[1]湖南大学,环境科学与工程学院,长沙410082 [2]广东石油化工学院,环境科学与工程学院,茂名525000

出　　处：《环境科学学报》2024年第7期57-68,共12页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.52200093,52270064,51978178);湖南省科技创新计划(No.2023RC3120);广东大学生科技创新培育专项资金资助项目(No.pdjh2022a0341)。

摘　　要：为进一步提高Ag_(3)PO_(4)的光催化活性并抑制其光腐蚀问题,本研究通过原位聚合和煅烧的方法合成了铁氮共掺杂的碳材料(Fe-N/C),并利用静电自组装法将Fe-N/C与Ag_(3)PO_(4)耦合制备出了Ag_(3)PO_(4)@Fe-N/C复合光催化材料,研究了其对水中四环素的催化降解性能特征和强化机制.结果表明,Ag_(3)PO_(4)@Fe-N/C具有比磷酸银单体更强的光催化活性及稳定性.优选的Ag_(3)PO_(4)@Fe-N/C复合催化剂在可见光辐照5 min后,对盐酸四环素的降解效率即可达到100%,催化反应速率常数达到1.399 min^(-1),是磷酸银单体的4.47倍.自由基捕捉实验和ESR测试结果表明,光催化反应过程中超氧自由基和光生空穴是降解盐酸四环素的关键活性物种.密度泛函理论(DFT)计算结果表明,与未掺杂碳材料相比,Fe-N/C具有更高的电荷密度和更低的功函数;同时,Fe-N/C可作为光生电子受体,加速复合催化剂界面电子转移,抑制光生电子和空穴的内部复合.本研究提供了一种可高效降解抗生素的可见光催化剂,并为磷酸银的性能优化提供了一种新的改性策略.In order to further improve the photocatalytic activity of Ag_(3)PO_(4) and suppress its photocatalytic corrosion,iron and nitrogen co-doped carbon materials (Fe-N/C) were synthesized through the methods of in-situ polymerization and calcination.Ag_(3)PO_(4)@Fe-N/C composite photocatalysts were prepared by coupling Fe-N/C with Ag_(3)PO_(4) via electrostatic self-assembly method.The photocatalytic degradation performance and mechanisms of Ag_(3)PO_(4)@Fe-N/C for tetracycline (TC) in aqueous solution were investigated.The results indicated that Ag_(3)PO_(4)@Fe-N/C possess superior photocatalytic activity and stability compared to Ag_(3)PO_(4).The optimal Ag_(3)PO_(4)@Fe-N/C composite catalyst could achieve a degradation efficiency of 100%for TC after5 min of visible light irradiation,with a catalytic reaction rate constant of 1.399 min^(-1),which was 4.47 times that of Ag_(3)PO_(4) monomer.The free radical capture experiment and ESR test results indicated that superoxide radicals and photogenerated holes were the key active species for the degradation of TC during the photocatalytic reaction process.The density functional theory (DFT) calculation results indicated that Fe-N/C has a higher charge density and lower work function compared to undoped carbon materials.Meanwhile,Fe-N/C could serve as a photogenerated electron acceptor,accelerating the interfacial electron transfer of composite catalysts,and inhibiting the internal recombination of photogenerated electrons and holes.This study provides a visible light catalyst that can efficiently degrade antibiotics and a new modification strategy for optimizing the performance of Ag_(3)PO_(4).

关 键 词：可见光催化剂 磷酸银 抗生素 自由基 光生空穴 

分 类 号：X131[环境科学与工程—环境科学] X703