Ag/Ag_(3)PO_(4)/NGQDs复合光催化剂的制备及其可见光催化性能研究  

Preparation of Ag/Ag_(3)PO_(4)/NGQDs composite photocatalysts and their visible light catalytic performance

作　　者：唐新德[1] 王津津 伍素云 刘水林 刘宁 龚升高 TANG Xinde;WANG Jinjin;WU Suyun;LIU Shuilin;LIU Ning;GONG Shenggao(School of Chemical and Environmental Engineering,Hunan Institute of Technology,Hengyang 421002)

机构地区：[1]湖南工学院,化学与环境工程学院,衡阳421002

出　　处：《环境科学学报》2024年第5期69-80,共12页Acta Scientiae Circumstantiae

基　　金：湖南省自然科学基金(No.2021JJ50084);湖南省教育厅项目(No.19A119,22A0631,21B0797,21C0813);国家自然科学基金(No.22108068)。

摘　　要：Ag_(3)PO_(4)的高载流子复合率和严重的光腐蚀极大地限制了其光催化应用.在此,通过简单的水热法制备了一系列银/磷酸银/氮掺杂石墨烯量子点(Ag/Ag_(3)PO_(4)/NGQDs)复合光催化剂,发现Ag和NGQDs可以大大提高Ag_(3)PO_(4)的光催化活性和稳定性,这归因于NGQDs接收电子和Ag的局域表面等离子体共振的协同效应.因此,Ag/Ag_(3)PO_(4)/NGQDs对甲基橙(MO)的降解表现出优异的光催化活性和稳定性.特别是,Ag/Ag_(3)PO_(4)/0.5%NGQDs对MO的降解速率常数分别是Ag_(3)PO_(4)和Ag_(3)PO_(4)/0.5%NGQDs的约2.5倍和1.6倍,且其对MO的光催化降解率在5次循环后仍保持在91.2%,而Ag_(3)PO_(4)/0.5%NGQDs和Ag_(3)PO_(4)分别仅保持在66.8%和31.3%.Ag/Ag_(3)PO_(4)/0.5%NGQDs复合光催化剂可见光降解MO过程中的主要活性物质是超氧自由基(·O_(2)^(-))和光生空穴(h^(+)).此外,Ag/Ag_(3)PO_(4)/0.5%NGQDs对罗丹明B、亚甲基蓝、苯酚和盐酸四环素等也表现出优异的光催化活性,这种高活性高稳定性Ag_(3)PO_(4)基复合光催化剂将可实际应用于废水处理.The high carrier recombination rate and severe photocorrosion of Ag_(3)PO_(4) greatly limit its photocatalytic application.Here,a series of silver/silver phosphate/nitrogen doped graphene quantum dot(Ag/Ag_(3)PO_(4)/NGQDs) composite photocatalysts were prepared by a simple hydrothermal method.It was found that Ag and NGQDs can greatly improve the photocatalytic activity and stability of Ag_(3)PO_(4),which is attributed to the synergistic effect of NGQDs with accepting electrons and Ag with slocalized surface plasmon resonance of electron.Therefore,Ag/Ag_(3)PO_(4)/NGQDs exhibited excellent photocatalytic activity and stability for the degradation of methyl orange(MO).Especially,the degradation rate constant of Ag/Ag_(3)PO_(4)/0.5%NGQDs for MO was about 2.5 times that of Ag_(3)PO_(4) and 1.6 times that of Ag_(3)PO^(4)/0.5%NGQDs.The photodegradation rate of Ag/Ag_(3)PO_(4)/0.5%NGQDs for MO still maintains 91.2% after 5 cycles,while Ag_(3)PO_(4)/0.5%NGQDs and Ag_(3)PO_(4) only maintains 66.8% and 31.3%,respectively.The main active substances in the visible light degradation of MO using Ag/Ag_(3)PO_(4)/NGQDs composite photocatalyst were superoxide radicals(·O_(2)^(-)) and photogenerated holes(h~+).In addition,Ag/Ag_(3)PO_(4)/0.5% NGQDs also exhibited excellent photocatalytic activity towards rhodamine B,methylene blue,phenol,and tetracycline hydrochloride.Such highly active and stable Ag_(3)PO_(4)-based composite photocatalyst will be practical for wastewater treatment.

关 键 词：Ag_(3)PO_(4) AG NGQD 光催化活性 稳定性 

分 类 号：O643[理学—物理化学] X703[理学—化学]