Dynamic Reconstruction of Cu‐Mediated ZnS/ZnO Heterointerfaces for Highly Efficient Noble‐Metal‐Free Photocatalytic Hydrogen Evolution

ABSTRACT

Engineering interfacial electronic structure to maximize active‐site density remains a central challenge in heterogeneous photocatalysis. Here, we report a defect‐mediated Cu ₂ O/ZnO nanocomposite with dual active sites, constructed via a sustainable deep eutectic solvent‐assisted strategy combined with photodeposition. Defect‐associated sites on ZnO promote the anchoring and stabilization of Cu species, consistent with proposed Cu‐V _o ‐Zn interfacial configurations that modulate the local electronic structure. The resulting system supports a proposed direct Z‐scheme charge‐transfer pathway that facilitates charge separation while maintaining redox capability. Notably, an in situ interfacial reconstruction during photocatalysis, accompanied by Zn─S bond formation, further activates the catalyst by generating Cu‐mediated ZnS/ZnO heterointerfaces. The reconstructed catalyst achieves a hydrogen evolution rate of 53.94 mmol g ^{− 1} h ^{− 1} under UV–vis light irradiation, representing a 4.60‐fold enhancement over the additive‐free system, while its visible‐light driven hydrogen evolution rate is approximately 200 times higher than that of pristine V _o ‐ZnO. These results demonstrate that defect‐driven interfacial reconstruction offers an effective strategy for designing photocatalysts for hydrogen evolution without noble‐metal cocatalysts.