p-Cu2S/n-ZnxCd1−xS nanocrystals dispersed in a 3D porous graphene nanostructure: an excellent photocatalyst for hydrogen generation through sunlight driven water splitting
p-Cu2S/n-ZnxCd1−xS nanocrystals dispersed in a 3D porous graphene nanostructure: an excellent photocatalyst for hydrogen generation through sunlight driven water splitting
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DOI：
10.1039/c6cy02469f
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发表时间：
2017-03
影响因子：
5
通讯作者：
Chunchun Wang;Je-Wei Chang;Shih‐Yuan Lu
中科院分区：
文献类型：
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作者：
Chunchun Wang;Je-Wei Chang;Shih‐Yuan Lu
开发了一种鸡尾酒策略来设计用于高性能太阳光驱动的光催化分解水制氢的复合半导体光催化剂。它包括带隙调谐，p-n结的形成，和p-n结在3D良好连接的导电支撑中的分散。在模拟太阳光100 mA cm−2的照射下，Zn0.71Cd0.29S的析氢速率比CdS提高了四倍以上，13 μmol h−1比2.7 μmol h−1，通过复合和带隙调节。通过将p型Cu 2S与n型Zn 0. 71 Cd 0. 29 S复合形成p-Cu 2S/n-Zn 0. 71 Cd 0. 29 S复合纳米晶，进一步提高了电荷分离，从13 μmol h-1提高到43. 4 μmol h-1。通过将p-Cu 2S/n-Zn 0. 71 Cd 0. 29 S复合纳米晶体分散在三维高导电多孔石墨烯纳米结构中，实现了更多的改进，将析氢速率提高到60. 1 μmol h−1。多孔石墨烯纳米结构吸引光诱导电子以进一步改善所涉及的电荷分离。因此，利用这种混合物材料设计实现了相对于CdS（用于水分解的最知名的太阳光响应光催化剂）的一个数量级的氢生成改进。达到的最高比析氢速率为1202 μmol g−1 h−1，是基于金属硫化物的太阳光驱动水分解的最高速率之一。
A cocktail strategy to design composite semiconductor photocatalysts for high performance sunlight driven photocatalytic water splitting for hydrogen generation was developed. It includes band gap tuning, p–n junction formation, and dispersion of p–n junctions in a 3D well-connected conductive support. An over fourfold improvement in the hydrogen evolution rate was achieved by Zn0.71Cd0.29S over CdS, 13 vs. 2.7 μmol h−1 under irradiation with simulated sunlight at 100 mA cm−2, through compositing and thus band gap tuning. A further improvement, from 13 to 43.4 μmol h−1, was achieved by compositing p-type Cu2S with n-type Zn0.71Cd0.29S to form p-Cu2S/n-Zn0.71Cd0.29S composite nanocrystals, to greatly enhance charge separations. Even more improvements were realized, boosting the hydrogen evolution rate up to 60.1 μmol h−1, by dispersing the p-Cu2S/n-Zn0.71Cd0.29S composite nanocrystals in a 3D, highly conductive porous graphene nanostructure. The porous graphene nanostructure attracts the photo-induced electrons to further improve the involved charge separation. A one-order of magnitude improvement in hydrogen generation over CdS, the best known sunlight responsive photocatalyst for water splitting, was thus achieved with this cocktail material design. The highest specific hydrogen evolution rate achieved, 1202 μmol g−1 h−1, is among the highest for metal sulfide based sunlight driven water splitting.