Strong interfacial coupling of Ni5P4/ZnCdS Schottky junction enhanced charge separation for boosting photocatalytic hydrogen evolution

A robust Ni 5 P 4 /ZnCdS Schottky junction was successfully constructed via strong interfacial coupling between chemically bonded porous Ni 5 P 4 nanoflowers and ZnCdS, significantly boosting interfacial charge separation and photocatalytic hydrogen evolution . • Ni 5 P 4 /ZnCdS Schottky junction was constructed via strong interfacial coupling. • Ni 5 P 4 nanoflowers effectively prevent the aggregation of ZnCdS through their three-dimensional structure. • Directional transfer channel formed by Ni-S bonds in the Ni 5 P 4 /ZnCdS Schottky junction. • The Schottky heterojunction were elucidated through DFT and in-situ XPS characterization. • The optimized 20 % Ni 5 P 4 /ZnCdS exhibits excellent PHE activity (34.92 mmol g -1 h −1 ). Constructing heterojunctions with high photogenerated carrier separation efficiency is an effective means to improve the performance of photocatalytic hydrogen production. In this work, a robust Ni 5 P 4 /ZnCdS Schottky junction was successfully constructed via strong interfacial coupling between chemically bonded porous Ni 5 P 4 nanoflowers and ZnCdS, significantly boosting interfacial charge separation and photocatalytic hydrogen evolution (PHE). Porous Ni 5 P 4 nanoflower was prepared by in situ low temperature phosphating calcination method, which can effectively prevent the aggregation of ZnCdS via its three-dimensional structure and provide abundant active and adsorption sites for PHE. In addition, chemically bonded Ni 5 P 4 and ZnCdS form tight electron transfer channels through Ni-S bonds at the Ni 5 P 4 /ZnCdS interface, accelerating the directional transfer of electrons at the interface and achieving better interface coupling. The Tafel slope indicates that Ni 5 P 4 /ZnCdS has excellent reaction kinetics. The electron transfer mechanism and Schottky heterojunction were elucidated through density functional theory (DFT) and in-situ XPS characterization. And the Schottky barriers at the Ni 5 P 4 /ZnCdS interface effectively prevent the recombination of photogenerated carriers, thereby improved the PHE activity. Consequently, the optimized 20 % Ni 5 P 4 /ZnCdS shows excellent PHE activity (34.92 mmol g −1 h −1 ) with high AQE of 13.56 % at 450 nm, which is 14.2 times higher than ZnCdS (2.46 mmol g −1 h −1 ). And exceptional photocatalytic stability of 20 % Ni 5 P 4 /ZnCdS was consistently maintained over multiple operational cycles. This work furnishes valuable strategy to construct Schottky junctions for enhancing PHE ability.