采用尿素沉积法制备了Au/TiO2/MoS2等离子体复合光催化剂.通过光催化产氢实验,在10％(φ,体积分数)甘油水溶液为牺牲剂条件下,研究了不同MoS2含量、Au固载2％(w,质量分数)时,Au/TiO2/MoS2 (ATM)复合样品的光催化产氢活性.结果表明,当MoS2含量为0.1％(w)时,复合样品ATM0.1显示出最高的光催化产氢活性,其产氢速率达到708.85 pmol.h-1,是TiO2/MoS2 (TM)两相复合样品中光催化活性最高样品TM6.0产氢速率的11倍.三相复合样品显示增强光催化产氢活性主要是由于吸附在TiO2/MoS2层状复合材料上的Au纳米颗粒具有表面等离子共振效应,能强烈吸收波长范围550-560 nm的可见光,诱导产生光生电子,金纳米颗粒上的电子受到激发后转移到TiO2导带上,TiO2导带上的电子传递给片状MoS2,最终在MoS2上催化氢气产生.%Au/TiO2/MoS2 plasmonic composite photocatalysts were synthesized via deposition-precipitation with urea.The photocatalytic activities of the prepared samples were evaluated by performing hydrogen production experiments under Xe lamp irradiation with a 10％ (φ,volume fraction) glycerol aqueous solution as the sacrificial agent.The results showed that the optimal content of MoS2 in the Au/TiO2/MoS2 composite is 0.1％ (w,mass fraction) and the corresponding H2 production rate was 708.85 iJmol·h-1,which was almost 11 times higher than that of TM6.0 with the strongest photocatalytic activity in the all binary TiO2/MoS2 composites.The enhanced photocatalytic activity of the ternary Au/TiO2/MoS2 composites is mainly due to the surface plasmon resonance of the supported Au nanoparticles absorbed on the TiO2/MoS2 layered composite,which show an intense absorption maximum centered around 550-560 nm and induce the photoexcitation of electrons.Meanwhile,the electrons excited by surface plasmon resonance of Au could be injected into the conduction band of TiO2,and they were then transferred to the edges of MoS2 for catalyzing the production of H2.
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