聚乙烯醇改性磷酸银的光催化活性研究

Study on Photocatalytic Activity of Silver Phosphate Modified by Polyvinyl Alcohol

在制备的磷酸银表面吸附少量的聚乙烯醇(PVA),并通过热处理制备了DPVA/Ag3PO4复合材料。使用傅立叶红外光谱法(FT-IR)和荧光光谱法(PL)对DPVA/Ag3PO4复合材料进行表征。分析得知,经聚乙烯醇复合改性的DPVA/Ag3PO4复合微粒中存在共轭结构,光生电子-空穴对复合率降低,光催化活性得到显著提高。研究了不同条件(复合比例、热处理温度、热处理时间)下制备的复合光催化剂在可见光下催化降解甲基橙的光催化性能。当PVA与Ag3PO4质量比为1:4000,热处理温度为190℃,热处理1 h时光催化效果最好。

A small amount of polyvinyl alcohol(PVA)was adsorbed on the surface of the prepared silver phosphate,and the DPVA/Ag3PO4 composite was prepared by heat treatment.The DPVA/Ag3PO4 composite was characterized and analyzed by Fourier transform infrared spectroscopy(FT-IR)and fluorescence spectroscopy(PL).Analysis shows that the conjugate structure exists in DPVA/Ag3PO4 composite particles modified by polyvinyl alcohol composite,the recombination rate of photo-generated electron-hole pairs reduces,and the photocatalytic activity is significantly improved.The visible-light photocatalytic activity of the composite photocatalyst prepared under different conditions(including compound ratio,temperature and time of heat treatment)for the degradation of Methyl orange under visible light was studied.The results show that the obtained DPVA/Ag3PO4 composite materials showed optimal photocatalytic activities when the mass proportion of PVA and silver phosphate was 1:4000,heated at 190℃ for 1 h.