New insight into the selective photocatalytic oxidation of RhB through a strategy of modulating radical generation
作者:Huijun Liang、Shengnan Liu、Hucheng Zhang、Xiaobing Wang、Jianji Wang
DOI:10.1039/c8ra01810c
日期:——
hydroxyl radicals (·OH) and superoxide anion radicals (·O2−) at different reaction stages so that the overoxidation of RhB and Rh-110 were repressed. Therefore, the transient state protection mechanism of selective oxidation of RhB was proposed to explain the reaction selectivity for Rh-110. Although the effects of both ·O2− and ·OH are important during the photocatalytic selective oxidation of RhB,
罗丹明 B (RhB) 经常被用作模型污染物,但其光催化机制仍存在争议。在此,将Ag NPs夹在CdS QD和无定形TiO 2 (a-TiO 2 )之间,旨在构建具有高选择性氧化活性的CdS/Ag/a-TiO 2催化剂。当使用罗丹明B(RhB)作为模型有机化合物时,CdS/Ag/a-TiO 2复合材料不仅可以调节自由基的产生,而且可以将RhB向罗丹明110(Rh-110)的转化率提高至高达可见光照射80分钟时为82%。一系列自由基清除实验表明,CdS/Ag/a-TiO 2复合材料可以在不同反应阶段调节羟基自由基(·OH)和超氧阴离子自由基(·O 2 - )的作用,从而使RhB和RhB的过度氧化。 Rh-110 被抑制。因此,提出了RhB选择性氧化的瞬态保护机制来解释Rh-110的反应选择性。尽管·O 2 -和·OH在RhB的光催化选择性氧化过程中都很重要,但当·O 2 -的影响大于·OH时