CdS纳米片与纳米线负载Au_(25)纳米团簇光催化苯甲醇无氧脱氢制苯甲醛反应的研究

Directing the CdS nanosheet and nanowire to high efficiency for photocatalytic anaerobic dehydrogenation of benzyl alcohol to benzaldehyde by depositing Au_(25) nanoclusters

光催化苯甲醇直接脱氢制苯甲醛是一种利用太阳能合成精细化学品的同时生成氢气的节能途径。负载型半导体CdS基催化剂是该反应的一类典型的光催化剂。文献报道CdS的形貌对光催化水分解的性能有明显的影响,但其在光催化苯甲醇无氧脱氢制苯甲醛反应中的形貌效应研究报道极少。本工作合成了纳米片状(NS)和纳米线状(NW)两种不同形貌的CdS,发现CdS-NS表现出比CdS-NW更高的转化苯甲醇的光催化活性,但这两种催化剂对苯甲醛的选择性非常低。通过在CdS-NS和CdS-NW上负载Au_(25)纳米团簇,光催化苯甲醇无氧脱氢制苯甲醛反应的活性和选择性明显提高,并显著减弱了CdS载体的形貌对催化反应性能的影响。以上结果为设计合成精细化学品的高效光催化剂提供了参考。

The photocatalysis of direct dehydrogenation of benzyl alcohol to benzaldehyde is an energy saving way to synthesize fine chemicals and pure hydrogen by using solar energy.The CdS-based catalysts were one of the typical kinds of photocatalysts for this reaction.The morphology of CdS could be easily tuned,which could greatly influence the photocatalytic performances.However,the morphology effect of CdS on the photocatalytic behaviour of the direct dehydrogenation of benzyl alcohol has not been investigated yet.In this work,we synthesized CdS with two different morphologies(nanosheet(NS)and nanowire(NW))and found the CdS-NS showed much higher photocatalytic activity for converting the benzyl alcohol than the CdS-NW,but the selectivity to benzaldehyde over the two supports was very low.By depositing Au_(25) nanoclusters on the CdS-NW and CdS-NS,the morphology effect of the CdS support could be mitigated and their catalytic activity and selectivity could be greatly boosted for the photocatalytic anaerobic dehydrogenation of benzyl alcohol to benzaldehyde and H2.The results of this work would provide new insight into the design of efficient photocatalysts for synthesizing fine chemicals.