Synergetic interfacial charge transfer with Z-scheme heterostructure and S-Mo-S linkage in one-pot synthesized SnIn4S8/MoS2 for efficient photocatalytic activity

Construction of high-efficiency scheme towards interfacial charge transfer is of great value to suppress the spatial carrier recombination and thus to develop advanced heterogeneous photocatalysts for environmental remedia-tion. Herein, a novel Z-scheme SnIn4S8/MoS2 with interfacial S-Mo-S bond was synthesized by a facile one-step hydrothermal method. The prepared optimal SnIn4S8/MoS2 heterostructure (SIS/MS-24) exhibited significantly enhanced visible-light photocatalytic activities for crystal violet degradation and Cr(VI) reduction compared with individual materials. The boosted photocatalytic performance was primarily attributed to the Z-scheme charge transfer mechanism certificated by the trapping experiments, ESR (electron spin resonance) test, and DFT (density functional theory) calculation. What's more, the formation of S-Mo-S bond between SnIn4S8 and MoS2 acted as a specific bridge to further promote the Z-scheme channel for charge transport at the interface. This synergy of Z-scheme heterostructure and covalent S-Mo-S linkage greatly accelerated the separation of electron-hole pairs. Additionally, the SIS/MS-24 composite also displayed good stability even after five cycles of testing experiments. This work provides a novel way to design and fabricate efficient Z-scheme photocatalysts for water purification.

Automated summary

Construction of efficient interfacial charge transfer schemes is crucial for developing advanced heterogeneous photocatalysts. In this study, a novel Z-scheme SnIn4S8/MoS2 heterostructure with interfacial S-Mo-S bond was synthesized. The optimized heterostructure exhibited significantly enhanced visible-light photocatalytic activities. The improved performance was attributed to the Z-scheme charge transfer mechanism and the formation of S-Mo-S bond, which acted as a bridge for charge transport at the interface. This work provides a novel way to design efficient Z-scheme photocatalysts for water purification.