Spatially Separating Redox Centers and Photothermal Effect Synergistically Boosting the Photocatalytic Hydrogen Evolution of ZnIn S Nanosheets.

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 S nanosheets is realized by designing a ternary Co S @ZnIn S @PdS (CS@ZIS@PS) hollow tubular core-shell structure. Particularly, Co S and PdS functionally serve as the reduction and oxidation cocatalysts, respectively. Experimental results confirm that the spatial separation of Co S 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 evolution rate of 11407 µmol g h , and the apparent quantum efficiency reaches 71.2% at 420 nm, which is one of the highest values among ZnIn S 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.