Ag3PO4/BiPO4复合光催化剂的制备及其降解罗丹明B的研究

摘要

A series of Ag3PO4/BiPO4composite photocatalysts with different doping proportion of BiPO4and Ag3PO4were synthesized by a hydrothermalmethod at different pH. The photocatalytic activity was investigated for deg-radation of Rhodamine B. The results shows that the photocatalystprepared by hydrothermal method at pH =7 and Ag3PO4/BiPO4composite ratio at 4:3 has the best catalytic performance. The degradation rate of rhodamine B reaches 61% after 180 min reaction, which is 27% higher than pure phase BiPO4. The samples are characterized by XRD, SEM and ultraviolet-visible diffuse reflection(UV-Vis DRS),which indicates that the bandgap width of catalyst de-creases,the more monoclinic type of BiPO4increases and the efficiency of photo-generated electrons and holes become lower. All of these properties canimprove the activity of degradation Rhodamine B.%采用水热法合成复合Ag3PO4/BiPO4光催化剂,考察不同pH和不同复合比例下合成的光催化剂对溶液中罗丹明B的光催化降解性能,并与BiPO4进行对比.结果表明:在 pH=7,复合比例Ag3PO4/BiPO4摩尔比为4:3条件下水热制备的Ag3PO4/BiPO4对可见光的利用率最高,催化性能最好;降解180 min后,对罗丹明B的降解率达到61%,较纯相BiPO4提升了27%.本文还利用 XRD、SEM和紫外可见漫反射(UV-Vis DRS)等测试手段对合成的样品进行表征,分析得出复合Ag3PO4之后,催化剂的禁带宽度变窄,并出现较多的独居石晶型BiPO4,光生电子与空穴复合效率变低,从而使复合材料的光催化降解罗丹明B的能力得到提升.