Applied Catalysis A: General, Vol.578, 70-82, 2019
Construction of efficient solar-light-driven quaternary Ag3VO4/Zn-3(VO4)(2)/Zn2V2O7/ ZnO heterostructures for removing organic pollutants via phase transformation and in-situ precipitation route
High efficient solar-light-driven heterogeneous photocatalysts are crucial for utilizing solar energy to deal with environmental problem. Herein, a novel Ag3VO4/Zn-3(VO4)(2)/Zn2V2O7/ZnO quaternary heterojunction (Ag3VO4/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 Ag3VO4, Zn-3(VO4)(2) and Zn2V2O7 semiconductors greatly strengthened the light harvesting and suppressed the recombination of photoinduced electron-hole pairs in Ag3VO4/Zn-V-O quaternary heterojunction, producing more (OH)-O-center dot and O-center dot(2)- radicals to participate in decomposing the organic pollutants. Under simulate solar light illumination, Ag3VO4 and Zn-V-O almost show no activity for phenols decomposition, however, 86%, 70% and 80% degradation rates were obtained over 50%Ag3VO4/Zn-V-O for bisphenol A, phenol and p-chlorophenol. Similar very high activity was observed over 50%Ag3VO4/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.
Keywords:Quaternary heterojunction;Phase transformation;In-situ precipitation;Solar-light-driven;Organic pollutant degradation