Construction of hierarchical core-shell Z-scheme heterojunction FeVO4@ZnIn2S4 for boosted photocatalytic degradation of tetracycline

Abstract

Constructing core-shell heterojunction and designing hierarchical structures have been considered as efficient strategies for enhancing the activity and stability of photocatalysts. Herein, a novel hierarchical core-shell Z-scheme heterojunction FeOV4@ZnIn2S4 was prepared via the in-situ growth of ZnIn2S4 on the surface of FeVO4 submicron bar with a facile solvothermal method. The formation of the hierarchical core-shell heterostructure between FeVO4 and ZnIn2S4 improved light-harvesting ability and promoted the separation of photoinduced electron-hole pairs. The prepared FeOV4@ZnIn2S4 exhibited superior photocatalytic activity toward tetracycline. The removal efficiency of tetracycline reached up to 90.8% within 120 min. The degradation rate were 5.75 and 2.06 times that of FeVO4 and ZnIn2S4, respectively. Furthermore, Z-Scheme charge transfer mechanism at the interface between FeVO4 and ZnIn2S4 was proposed based on the results obtained from radical trapping test and electron spin resonance (ESR), which revealed that •O2−, •OH and h+ all act as active species in photocatalytic reaction. This work can bring a strategy for the preparing highly efficient heterojunction photocatalysts.