Construction of efficient solar-light-driven quaternary Ag3VO4/Zn3(VO4)2/Zn2V2O7/ ZnO heterostructures for removing organic pollutants via phase transformation and in-situ precipitation route

Abstract High efficient solar-light-driven heterogeneous photocatalysts are crucial for utilizing solar energy to deal with environmental problem. Herein, a novel Ag 3 VO 4 /Zn 3 (VO 4)2 / Zn 2 V 2 O 7 /ZnO quaternary heterojunction (Ag 3 VO 4 /Zn-V-O) was constructed by a phase transformation and in-situ precipitation process. This quaternary heterojunction photocatalyst was applied to efficiently remove some typical organic pollutants, e.g. phenols (bisphenol A, p-chlorophenol, phenol) and azo dyes (rhodamine B, methyl orange, acid orange II and methylene blue). The well matched energy level structure among Ag 3 VO 4 , Zn 3 (VO 4 ) 2 and Zn 2 V 2 O 7 semiconductors greatly strengthened the light harvesting and suppressed the recombination of photoinduced electron-hole pairs in Ag 3 VO 4 /Zn -V-O quaternary heterojunction, producing more OH and O 2 − radicals to participate in decomposing the organic pollutants. Under simulate solar light illumination, Ag 3 VO 4 and Zn-V-O almost show no activity for phenols decomposition, however, 86%, 70% and 80% degradation rates were obtained over 50%Ag 3 VO 4 /Zn -V-O for bisphenol A, phenol and p-chlorophenol. Similar very high activity was observed over 50%Ag 3 VO 4 /Zn -V-O for azo dyes degradation (95% for RhB, 50% for MO, 78% for orange II and 100% for MB). This work could afford interesting insight into designing advanced photocatlysts for applying solar light to environmental purification.