通过在可见光照射下加载MoS2作为Cocatalyst来增强CdS上的光催化H2进化
Xu Zong1, Hongjian Yan, Guopeng Wu
1State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Journal of the American Chemical Society
|May 14, 2008
概括
将少量二硫化 (MoS2) 添加到硫化 (CdS) 中,可显著增加光催化 (H2) 的产生. 这种MoS2/CdS催化剂的性能甚至超过了H2进化的贵金属催化剂.
科学领域:
- 材料科学 材料科学 材料科学
- 光催化作用的光催化
- 气生产 气生产
背景情况:
- 光催化生产是可再生能源的一个关键领域.
- 硫化 (CdS) 是一种已知的光催化剂,但通常需要催化剂来提高效率.
研究的目的:
- 为了研究加载二硫化物 (MoS2) 作为共催化剂对CdS对增强光催化H2生产的影响.
- 为了比较MoS2/CdS催化剂与装有贵金属的CdS和CdS的性能.
主要方法:
- 合成MoS2/CdS复合光催化剂的合成.
- 在可见光照射下从乳酸改制中评估H2进化速率.
- 与CdS和贵金属改性CdS催化剂的比较.
主要成果:
- 将少量 (0.2重量%) 的MoS2加载到CdS上,显著提高了H2生产率,高达36倍.
- 这种MoS2/CdS催化剂的活性高于含有贵金属 (Pt,Ru,Rh,Pd,Au) 的CdS.
- 可见光辐射对光催化反应有效.
结论:
- 这种MoS2/CdS复合物是H2生产的高效光催化剂.
- 增强的活性归因于MoS2和CdS之间形成的异质连接以及MoS2的H2激活特性.
- MoS2 是一个有前途的共催化剂,可以提高半导体光催化剂的性能,并有可能取代昂贵的贵金属.
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