Spatially Separating Redox Centers and Photothermal Effect Synergistically Boosting the Photocatalytic Hydrogen Evolution of ZnIn<sub>2</sub>S<sub>4</sub> Nanosheets
Man Wang, Gongxin Zhang, Zhongjie Guan, Jianjun Yang, Qiuye Li
Abstract
Abstract Spatially separated loading of reductive and oxidative cocatalysts is a useful strategy for expediting charge separation and surface reaction kinetics, which are two key factors for determining the photocatalytic efficiency. However, loading the spatial separation of dual cocatalysts on a 2D photocatalyst is still a great challenge. Herein, decorating the spatial separation of oxidative and reductive cocatalysts on ZnIn 2 S 4 nanosheets is realized by designing a ternary Co 9 S 8 @ZnIn 2 S 4 @PdS (CS@ZIS@PS) hollow tubular core‐shell structure. Particularly, Co 9 S 8 and PdS functionally serve as the reduction and oxidation cocatalysts, respectively. Experimental results confirm that the spatial separation of Co 9 S 8 and PdS cocatalysts not only efficiently improve charge separation and accelerate surface reduction–oxidation kinetics, but also generate a photothermal effect to further enhance charge transfer and surface reaction kinetics. As a result, the optimized CS@ZIS@PS yields a remarkable H 2 evolution rate of 11407 µmol g −1 h −1 , and the apparent quantum efficiency reaches 71.2% at 420 nm, which is one of the highest values among ZnIn 2 S 4 so far. The synergistic effect of spatially separated dual cocatalysts and photothermal effect may be applied to other 2D materials for efficient solar energy conversion.