AgCl/BiFeO3复合光催化剂的制备及其光催化性能

Synthesis of AgCl/BiFeO_3 composites with enhanced photocatalytic properties

采用水热法合成了BiFeO_3,使用光还原技术将AgCl沉积在BiFeO_3表面,制备了具有可见光催化活性的AgCl/BiFeO_3复合光催化剂,并利用XRD、SEM和UV-Vis DRS等分析了AgCl/BiFeO_3异质结的物相、表面结构和光响应性等性能。结果表明,AgCl的沉积不仅改善了BiFeO_3的表面结构,有效促进光生电子的迁移;而且扩宽了BiFeO_3的光响应范围,提高了BiFeO_3的可见光响应能力。以光催化降解模拟染料废水的效果评价其可见光催化性能。结果表明,Ag与Bi物质的量比为1∶2时,AgCl/BiFeO_3复合光催化剂对亚甲基蓝的降解效果最佳,光照210 min,降解率可达92.5%。AgCl/BiFeO_3复合光催化剂具有良好的光催化稳定性,循环使用5次后,降解率仍能达到80%以上。

BiFeO3 was prepared by hydrothermal method,and then,AgCl/BiFeO3 composites with visible light photocatalytic activity was synthesized by photoreduction deposition of AgCl onto BiFeO3.The phase,surface structure and light response was characterized by the XRD,SEM,and DRS UV-Vis.Due to the deposition of AgCl,surface structure of BiFeO3 was improved,and the recombination of photogenerated electron/hole pair was effectively suppressed.Furthermore,the structure broadened the response range of visible light.The photocatalytic performance was investigated by degradation of simulated dye wastewater.The results showed that the degradation conversion to methylene blue on AgCl/BiFeO3 with Ag∶Bi=1∶2 was 92.5%in 210min,higher than that of AgCl and BiFeO3.AgCl/BiFeO3 had good photocatalytic stability,and the degradation rate could reach more than 80%after recycling 5 times.