Gradient Hydrogen Migration Modulated with Self-Adapting S Vacancy in Copper-Doped ZnIn2S4 Nanosheet for Photocatalytic Hydrogen Evolution

作者：Shuqu Zhang, Zhifeng Zhang, Yanmei Si, Bing Li, Fang Deng, Lixia Yang, Xia Liu, Weili Dai, Shenglian Luo · 发表于：ACS Nano · 年份：2021 · DOI：10.1021/acsnano.1c05834 · 被引用次数：399 · 研究领域：Advanced Photocatalysis Techniques、Perovskite Materials and Applications、ZnO doping and properties

It is a challenge to regulate charge flow synergistically at the atomic level to modulate gradient hydrogen migration (H migration) for boosting photocatalytic hydrogen evolution. Herein, a self-adapting S vacancy (Vs) induced with atomic Cu introduction into ZnIn 2 S 4 nanosheets was fabricated elaborately, which can tune charge separation and construct a gradient channel for H migration. Detailed experimental results and theoretical simulations uncover the behavior mechanism of Vs generation with Cu introduction after substituting a Zn atom tendentiously. Cu–S bond shrinkage and Zn–S bond distortion are presented around Vs areas. Besides, Vs induced by Cu introduction lowers the internal electric field to restrain electron transmission between layers, which are enriched on the Vs area because of the lower surface electrostatic potential. Atomic Cu and Vs show a synergistic effect for regulating regional charge separation due to the Cu dopant being a hole trap and Vs being an electron trap. The channels for H migration with gradient Δ G H 0 are constructed by different S atom sites, which are modulated by Vs. Gradient H migration driven by a photothermal effect occurs on an identical surface without striding across a heterogeneous interface, which is a valid pathway with lower resistance for boosting H 2 release. Ultimately, 5 mol % Cu confined in ZnIn 2 S 4 nanosheets achieves an optimum photocatalytic hydrogen evolution activity of 9.8647 mmol g –1 h –1, which is 14.8 time...