铁掺杂高结晶氮化碳光催化降解萘普生协同产氢的研究  

Fe doped highly crystalline carbon nitride for photocatalytic degradation of NPX coupled with hydrogen evolution

作　　者：王盈霏 李传浩 刘国光[3] WANG Yingfei;LI Chuanhao;LIU Guoguang(Department of Social and Ecological Civilization,Party School of the Guangdong Provincial Committee of Communist Party of China(Guangdong Institute of Public Administration),Guangzhou 510053;School of Environmental Science and Engineering,Sun Yat-sen University,Guangzhou 510006;School of the Environment and Engineering,Guangdong University of Technology,Guangzhou 510006)

机构地区：[1]中共广东省委党校社会和生态文明教研部(广东行政学院),广州510053 [2]中山大学环境科学与工程学院,广州510006 [3]广东工业大学环境科学与工程学院,广州510006

出　　处：《环境科学学报》2024年第12期78-90,共13页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.21906029,22076029,22176042);广州市社科规划项目(No.2023GZGJ26);中共广东省委党校(广东行政学院)重大攻关项目(No.XYZDGG202402)。

摘　　要：以二聚氰胺为前驱体,采用金属氯盐辅助熔盐处理策略制备出铁掺杂高结晶氮化碳光催化剂(CCN/Fe),并通过高分辨透视电子显微镜(HR-TEM)、X射线衍射(XRD)、氮气吸脱附测试(BET)、傅里叶变换红外光谱(FT-IR)、光电子能谱(XPS)对其形貌、组成和结构进行表征.结果显示,CCN/Fe具有合适的能带结构,能够同时满足水体污染物氧化降解和水还原制氢的热力学需求.同时,Fe元素的引入有效提高了光生载流子的分离和迁移效率.以萘普生(NPX)为目标污染物,研究该体系的光催化反应性能.实验发现,经过40 min的可见光照,CCN/Fe对NPX的去除率可达90.2%.此外,光催化产氢反应结果表明,在三乙醇胺和甲醇两种牺牲剂存在下,CCN/Fe均表现出优异的产氢性能.基于此,本文构筑了光催化NPX降解协同产氢反应体系,结果表明,CCN/Fe光催化剂在可见光照下能够同步实现NPX高效降解与协同产氢,产氢效率和NPX的降解率分别达820.5μmol·g^(-1)·h^(-1)和78.9%.实验和理论计算结果表明,CCN/Fe体系产生的光生电子将水分子还原成H_(2),而光生空穴则将水氧化成H_(2)O_(2).原位产生的H_(2)O_(2)随后被分解成·OH,并进攻NPX分子导致其降解.循环稳定性实验和表征表明,CCN/Fe通过4次循环利用后仍能保持良好的光催化性能.值得注意的是,CCN/Fe光催化体系在多种自然水体中均能表现出优异的光催化降解协同制氢性能,表明其具有较好的应用前景.In this study,iron-doped highly crystalline nitrogen-doped carbon(CCN/Fe)photocatalyst is synthesized via a metal chloride-assisted molten salt treatment strategy.The morphology,composition and structure of the as-prepared CCN/Fe are investigated by HR-TEM,XRD,BET,FT-IR and XPS.Characterization results show that CCN/Fe exhibits appropriate conduction and valence band potentials that can simultaneously meet the thermodynamic requirements of photocatalytic degradation of NPX and hydrogen evolution.In addition,the migration and separation efficiencies of photogenerated carriers can be effectively improved following the introduction of Fe element.The photocatalytic performances of as-prepared catalysts are then evaluated by using naproxen(NPX)as the target pollutant.The results show that the removal rate of NPX over CCN/Fe reaches 90.2%after 40min of visible light irradiation.In addition,the CCN/Fe demonstrates excellent photocatalytic performance toward hydrogen evolution in the presence of sacrificial agents(i.e.,triethanolamine and methanol).Thus,a photocatalytic system for the degradation of NPX coupled with hydrogen evolution is established.The results exhibit that highly efficient degradation of NPX and hydrogen evolution can be simultaneously achieved in the CCN/Fe photocatalytic system under the irradiation of visible light,delivering the H_(2) evolution rate and NPX degradation efficiency of 820.5μmol·g^(-1)·h^(-1)and78.9%,respectively.Experimental and theoretical calculation results suggest that the photo-generated electron in CCN/Fe photocatalytic system is able to decompose the water molecule to produce hydrogen,while the photo-generated hole oxidize water molecule into H_(2)O_(2).The in situ generated H_(2)O_(2)subsequently decomposes into·OH,which attack the NPX molecule and lead to their degradation.Cycle and stability experiments show that CCN/Fe possesses excellent photocatalytic performance even after four cycles of reaction.Most importantly,the CCN/Fe photocatalytic system functions well even i

关 键 词：萘普生 铁掺杂高结晶氮化碳 光催化产氢 降解机理 

分 类 号：X703[环境科学与工程—环境工程]