ZnIn₂S₄ enwrapping CoP with phosphorus vacancies hollow microspheres for efficient photocatalytic hydrogen production

To address the pressing challenges of energy shortages and environmental sustainability, photocatalytic water splitting for hydrogen production has emerged as a promising strategy for solar energy conversion. While semiconductor catalysts exhibit significant potential in photocatalysis, their practical applications are hindered by limitations such as inefficient charge separation and insufficient active sites. Designing and preparing efficient, non-precious co-catalysts is therefore essential. In this work, we synthesized cobalt phosphide with phosphorus vacancy defects (vp-CoP) hollow microsphere co-catalysts and loaded them with indium zinc sulfide (ZnIn₂S₄) nanosheets to construct vp-CoP@ZnIn₂S₄ (vp-CoP@ZIS) heterojunction photocatalysts. Under visible light irradiation, the vp-CoP@ZIS photocatalyst achieved a hydrogen production rate of 7.4 mmol g^-1 h^-1, which was 7.6 times higher than that of pristine ZnIn₂S₄. This remarkable enhancement arises from the synergistic effects between vp-CoP and ZnIn₂S₄. Specifically, the introduction of single-atom phosphorus vacancies significantly improved electron transfer efficiency and promoted charge separation within the heterojunction. This innovative design and synthesis strategy underscores the potential of vp-CoP@ZIS as a robust photocatalyst for solar-driven hydrogen production, providing a sustainable pathway for efficient solar energy utilization.