AgI quantum dots synergistic double Z-type heterojunction for AgI/WO3/V2O5 with prominent photocatalytic degradation efficiency and antibacterial activity

Abstract

This study successfully prepared a double Z-scheme heterojunction composite photocatalysts AgI/WO₃/V₂O₅ with extremely high degradation performance for RhB and even photocatalytic bacteriostatic effect. TEM observations revealed uniformly distributed AgI quantum dots between the layers. These quantum dots exhibit a broad spectral absorption range, enhancing the catalyst's ability to absorb visible light. The double Z-scheme heterojunction facilitates the accumulation of electrons on the conduction band of AgI and holes on the valence band of V₂O₅, effectively promoting the separation of electron-hole pairs. The synergistic effect of the quantum dots and the double Z-scheme heterojunction further accelerates the separation and migration of charge carriers, significantly improving the degradation efficiency of dye molecules. The AgI/WO₃/V₂O₅ photocatalyst demonstrated excellent degradation performance for RhB, achieving a degradation rate of 98.6% merely in 20 min of visible light irradiation. The performance surpasses those V₂O₅-based composite photocatalyst reported in all previous literatures as we known. Additionally, the composite photocatalyst exhibited remarkable antibacterial activity against E. coli. After 60 min of visible light irradiation, almost no bacterial survival was observed, indicating its strong antibacterial capability. In summary, we have designed a novel AgI/WO₃/V₂O₅ composite material, which integrates a double Z-scheme heterojunction with a quantum dot structure and exhibits superior photocatalytic properties. This research not only provides new insights for the design of high-efficiency photocatalysts but also expands the application prospects of V₂O₅-based materials in fields such as photocatalysis and antibacterial applications.