Facile construction of a fascinating Z-scheme AgI/Zn3V2O8 photocatalyst for the photocatalytic degradation of tetracycline under visible light irradiation

Abstract

Solar-driven photocatalytic degradation undoubtedly represents a hopeful, sustainable together with effective alternative wastewater decontamination technology, however, exploiting highly efficient visible-light-induced photocatalysts for sewage remediation still exists a great challenge. Herein, a fascinating and unique AgI/Zn3V2O8 Z-scheme photocatalyst was rationally constructed by immobilizing AgI nanoparticles on the surface of flower-like Zn3V2O8 nanosheets using a facile precipitation approach. Multiple techniques were employed to uncover the structure, morphology, composition, optical and electrochemical properties of as-generated samples. As expected, the resultant AgI/Zn3V2O8 photocatalyst manifested greatly boosted the photocatalytic activity towards tetracycline (TC) degradation under visible light irradiation. Noticeably, the optimized AgI(20 wt%)/Zn3V2O8 photocatalyst displayed the largest removal efficiency of TC, which was around 2.1 and 2.5 folds higher than that of pristine Zn3V2O8 and AgI, separately. This improvement was due to the generated Z-scheme heterojunction between Zn3V2O8 and AgI with the intimate interfacial contact, which significantly promoting the spatial separation and migration efficiency of photoexcited charge carriers and maintaining the high redox potential at the same time. Furthermore, superoxide and hydroxyl radicals were identified as the main active species for TC degradation, and a possible degradation pathway of TC was also deduced. These findings may open a new avenue for reasonable design of high-efficiency Zn3V2O8-based Z-scheme heterojunction photocatalysts for the removal of antibiotics from wastewater.