Abstract: This study ingeniously synthesized a novel CdS/NiS hollow nanoflower sphere (HNS) using a one-step method to enhance photocatalytic hydrogen production activity. Compared to conventional preparation methods, this approach features seamlessly interfaced contact that facilitates efficient electron transfer across the interface. The internal hollow structure allows for multiple light reflections, maximizing light absorption, while the exterior shell and inner surfaces simultaneously offer active sites for reactions. The modification with non-noble metal NiS enables the extraction of electrons from CdS to the NiS surface, achieving rapid charge separation. Furthermore, adsorption-free energy calculations reveal that the NiS surface is more conducive to photocatalytic hydrogen generation, providing additional reaction active sites. The results demonstrate a hydrogen production rate of 2.18 mmol g^-1 h^-1 for CdS/NiS HNS, which is 9.48 times greater than that of pristine CdS. This work presents a novel approach for synthesizing seamlessly interfaced contacts between photocatalysts and cocatalysts, offering new insight into efficient one-step synthesis for enhanced photocatalytic performance.

Key words: Seamlessly contacted, Hollow nanoflower sphere, Photocatalytic hydrogen production, Cocatalyst