Zr-based metal–organic framework PCN-222@defective ZnIn2S4 core–shell Z-scheme heterojunctions toward efficient charge separation and optimized photocatalytic performance

Abstract

Interface engineering is vital for promoting photocatalytic performance. Here, a novel Zr-based metal–organic framework PCN-222@defective ZnIn₂S₄ with indium vacancy core–shell Z-scheme heterojunctions (PV_In-ZIS) was fabricated through a facile solvent-thermal method. The as-synthesized PV_In-ZIS showed a superior photocatalytic behavior than those of ZnIn₂S₄ with/without indium vacancies and PCN-222@ZnIn₂S₄ without indium vacancies. The structure of the material was characterized and analyzed by X-ray diffractometry, in situ X-ray electron spectrometry, electron paramagnetic resonance, etc. The optimized photocatalytic H₂ production rate of the material was up to 1.79 mmol g⁻¹ h⁻¹, several times higher than that of others. Furthermore, the photocatalytic degradation efficiency of tetracycline could reach 93.50% within 4 h. The enhancement in the photocatalytic performance could be ascribed to the formation of Z-scheme heterojunction among PCN-222 and ZnIn₂S₄ with indium vacancy promoting the spatial charge separation. The scarcely decreased photocatalytic performance after recycling indicated the high stability of PV_In-ZIS, which will be potentially applied in fields of energy and the environment.