In Situ Fabrication of Robust Cocatalyst-Free CdS/g-C3N4 2D-2D Step-Scheme Heterojunctions for Highly Active H2 Evolution
In Situ Fabrication of Robust Cocatalyst-Free CdS/g-C3N4 2D-2D Step-Scheme Heterojunctions for Highly Active H2 Evolution
复制标题
原位制造稳健的无助催化剂 CdS/g-C3N4 2D-2D 阶梯式异质结，用于高活性 H-2 演化
DOI：
10.1002/solr.201900423
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发表时间：
2019-11-14
期刊：
影响因子：
7.9
通讯作者：
Li, Xin
中科院分区：
文献类型：
--
作者：
Ren, Doudou;Zhang, Weinan;Li, Xin
半导体光催化剂高效分解水生成氢气是能源和环境领域的重要研究方向。本文采用水热法在2D-C3N4/g-C3N4纳米片上原位生长2D-2D CDS/g-C3N4阶梯式(S方案)异质结光催化剂。结果表明，在不使用任何助催化剂的情况下，二元硫化镉/0.7g-C3N4 S方案异质结的氢产率最高(15.3mmolg~(-1)h~(-1))，分别是纯硫化镉和g-C_3N_4的3.83倍和3060倍。在420 nm处，CDS/0.7G-C3N4的表观效率为6.86%。重要的是，所制备的CdS/0.7G-C3N4 S方案异质结在连续辐照21h后仍具有良好的稳定性，这种稳定性和活性的提高归功于S方案异质结的形成，它可以显著地加速界面电荷的分离，从而促进表面反应。无助催化剂的硫化镉/g-C3N42D-2D S方案异质结的设计有望成为在各种常规半导体NSS的基础上发展高活性氢气析出体系的一种有前途的途径。
Efficient H2O splitting for H-2 evolution over the semiconductor photocatalyst is a crucial strategy in the field of energy and environment. Herein, cocatalyst-free 2D-2D CdS/g-C3N4 step-scheme (S-scheme) heterojunction photocatalysts are fabricated through in situ hydrothermal growth of 2D CdS nanosheets (NSs) on 2D g-C3N4 NSs. The results clearly confirm that the binary CdS/0.7g-C3N4 S-scheme heterojunction shows the best H-2 production rate (15.3 mmol g(-1) h(-1)) without using any cocatalyst, which is 3.83 times and 3060 times higher than those of pure CdS and g-C3N4, respectively. The apparent efficiency of CdS/0.7g-C3N4 at 420 nm is 6.86%. Importantly, the as-prepared CdS/0.7g-C3N4 S-scheme heterojunction has good stability when continuously irradiated for 21 h. The improved stability and activity are attributed to the formation of the S-scheme heterojunction, which can markedly accelerate the interfacial charge separation for surface reaction. It is expected that the design of robust cocatalyst-free CdS/g-C3N4 2D-2D S-scheme heterojunction can become a promising approach to develop the highly active H-2 evolution systems based on various kinds of conventional semiconductor NSs.