一步还原法制备Bi/Bi_(2)MoO_(6)及其光催化性能研究

Facile one-step synthesis of Bi/Bi_(2)MoO_(6)reduction and photocatalyticapplication

论文通过乙二醇还原法制备Bi/Bi_(2)MoO_(6)光催化剂。通过XRD、SEM、FT-IR和BET技术对所制备样品物化结构和形貌进行分析,探究不同铋沉积量与光催化活性之间的构效关系。在模拟太阳光照射下,构筑的Bi/Bi_(2)MoO_(6)光催化剂对罗丹明B光催化降解性能明显优于Bi_(2)MoO_(6)单体,这归因于Bi和Bi_(2)MoO_(6)之间的协同作用有效的降低了光生电子-空穴对的复合率。最后通过紫外可见漫反射和自由基捕获实验对光催化降解机理过程进行探究,证明了超氧自由基和空穴是参与罗丹明B染料降解过程的两种活性化学物质,提出了可能的光催化机理,显示了Bi/Bi_(2)MoO_(6)复合材料在环境修复方面的巨大潜力。

Bi/Bi_(2)MoO_(6)photocatalyst was prepared by one-step reduction method with ethylene glycol.The phase,morphology and structure of the photocatalysts were characterized by XRD,SEM,FT-IR,BET and other test techniques,which explored the structure-activity relationship between different amounts of bismuth deposition and photocatalytic activity.The photocatalytic degradation of rhodamine B over Bi/Bi_(2)MoO_(6)was significantly better than that of the pure Bi_(2)MoO_(6)under simulated sunlight irradiation.After Bi_(2)MoO_(6)combined with Bi to form heterojunction,the recombination rate of photoelectron-hole pair was significantly reduced,thus greatly improving the photocatalytic degradation activity of rhodamine B over Bi/Bi_(2)MoO_(6).The SPR effect formed on the surface of bismuth metal and bismuth molybdate semiconductor was also one of the main contributions due to its local electromagnetic field enhancement.In addition,the free radical capture experiment also proved that superoxide radical and hole are two active chemical substances involved in the degradation process of rhodamine B dye,thus providing a possible photocatalytic mechanism.The Bi/Bi_(2)MoO_(6)photocatalyst composites have been proven to show great potential in environmental remediation.