MoS2/Graphene Cocatalyst for Efficient Photocatalytic H2 Evolution under Visible Light Irradiation
MoS2/Graphene Cocatalyst for Efficient Photocatalytic H2 Evolution under Visible Light Irradiation
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DOI：
10.1021/nn5019945
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发表时间：
2014-07-01
期刊：
影响因子：
17.1
通讯作者：
Ye, Jinhua
中科院分区：
文献类型：
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作者：
Chang, Kun;Mei, Zongwei;Ye, Jinhua
开发无贵金属助催化剂对于利用太阳能光催化分解水具有巨大的意义。在这里，我们报告了一种复合材料，由CdS纳米晶体生长在一个纳米级的二硫化钼/石墨烯混合物的表面上作为一个高性能的贵金属自由光催化剂在可见光照射下的H-2的演变。通过对各组分配比的优化，当MoS 2/石墨烯助催化剂的含量为2.0wt%、MoS 2与石墨烯的摩尔比为1：2时，MoS 2/G-CdS复合材料的光催化产氢活性最高。在Na 2S-Na 2SO 3溶液和乳酸溶液中测试并比较了MoS 2/G-CdS复合材料的光催化析氢活性。在420 nm处，乳酸溶液中的放氢速率为1.8 mmol/h，对应的AQE为28.1%，不仅高于Na_2S-Na_2SO_3溶液中的放氢速率1.2 mmol/h，而且远高于Pt/CdS在乳酸溶液中的放氢速率。并对相关机理进行了探讨。这种MoS 2/G-CdS复合材料有望成为一种高效、低成本的光催化析氢反应催化剂。
Exploiting noble-metal-free cocatalysts is of huge interest for photocatalytic water splitting using solar energy. Here we report a composite material consisting of CdS nanocrystals grown on the suface of a nanosized MoS2/graphene hybrid as a high-performance noble-metal-free photocatalyst for H-2 evolution under visible light irradiation. Through the optimizing of each component proportion, the MoS2/G-CdS composite showed the highest photo-catalytic H-2 production activity when the content of the MoS2/graphene cocatalyst is 2.0 wt % and the molar ratio of MoS2 to graphene is 1:2. The photocatalytic H-2 evolution activity of the proposed MoS2/G-CdS composite was tested and compared in Na2S-Na2SO3 solution and lactic acid solution. A 1.8 mmol/h H-2 evolution rate in lactic acid solution corresponding to an AQE of 28.1% at 420 nm is not only higher than the case in Na2S-Na2SO3 solution of 1.2 mmol/h but also much higher than that of Pt/CdS in lactic acid solution. The relative mechanism has been investigated. It is believed that this kind of MoS2/G-CdS composite would have great potential as a promising photocatalyst with high efficiency and low cost for photocatalytic H-2 evolution reaction.