以三聚氰胺和硝酸银为前驱体制备了不同银负载量的氮化碳复合材料,通过TEM、XRD、UV-Vis、XPS、PL等技术对催化剂进行表征,结果表明,银的引入改变了氮化碳的结构和性质。以盐酸多西环素为污染物,考察了不同负载质量分数的Ag/g-C₃N₄的光催化性能,结果表明,5.0%的Ag/g-C₃N₄对盐酸多西环素具有最佳的降解性能,在可见光下,Ag/g-C₃N₄在 40 min内去除了85%的盐酸多西环素(20.00 mg/L)。与g-C₃N₄[k=0.172 L/(mol·min)]相比,Ag/g-C₃N₄体系[k=4.42 L/(mol·min)]的降解速率常数提高了25.7倍。化学捕获实验表明,超氧自由基和空穴是主要的活性物种。

Carbon nitride composite materials (Ag/g-C₃N₄) with different silver doping amount are prepared by using melamine and silver nitrate as precursors,and characterized by means of TEM,XRD,UV-Vis,XPS,PL,etc.It is verified by the results that the structure and properties of carbon nitride are changed after silver doping.Taking doxycycline hydrochloride as a pollutant,the photocatalytic performance of Ag/g-C₃N₄ with different loading mass fraction is evaluated.It is found that 5.0% Ag/g-C₃N₄ shows the optimal degradation performance to doxycycline hydrochloride.Under visible light,85% of doxycycline hydrochloride (20.00 mg·L^-1) has been removed by Ag/g-C₃N₄ in 40 min.The degradation rate constant of Ag/g-C₃N₄ system reaches 4.42 L·mol^-1·min^-1,which is 25.7 times that of g-C₃N₄ (0.172 L·mol^-1·min^-1).It is verified by chemical capture experiment that superoxide radicals and holes are the main active species.

刘玉娇(2000-),女,硕士生,研究方向为环境光催化,1747233579@qq.com;何洁丽(1985-),女,博士,教授,研究方向为纳米光催化材料开发及应用,通讯联系人,hejieli@dali.edu.cn。