Integrating interfacial Ni-S bond-strengthened ohmic junctions with sulfur vacancies for simultaneous efficient photocatalytic norfloxacin degradation and H2 generation

Dual-functional photocatalysts (DFP) have shown remarkable advantages in converting solar energy into renewable H₂ while simultaneously remediating the environmental pollution. To achieve rapid separation and high utilization of the photogenerated charge carriers, it is crucial to establish robust atom-level interactions within a DFP heterostructure. In this context, a binary Ni₂P/d_s-Zn₃In₂S₆ photocatalyst was synthesized for synchronous norfloxacin degradation and H₂ production. Metallic Ni₂P was chemically anchored onto the d_s- Zn₃In₂S₆ surface to reduce the energy barrier for interfacial electron transfer. Sulfur vacancies were engineered within the Zn₃In₂S₆ lattice to facilitate the isolation of charge carriers. Resultantly, the composite photocatalyst, leveraging the synergistic effects of the Ni₂P cocatalyst, interfacial Ni-S bond-reinforced ohmic junctions and sulfur defects, exhibited 19.17-fold enhancements in H₂ release (2.32 mmol g⁻¹ h⁻¹) and 2.84-fold improvements in norfloxacin decomposition (98.38%) compared to pristine Zn₃In₂S₆. On the ground of Fukui function calculations and liquid chromatography-mass spectrometry results, four plausible pathways for photocatalytic norfloxacin degradation were proposed. It is anticipated that the collaborative strategy outlined in this work will provide valuable insights into the design of high-performance DFP.