Construction of Ag3PO4–TiO2 nano-heterostructure with excellent visible-light-driven photocatalytic activity for environmental applications

Nano-heterostructure constructed from Ag3PO4 and TiO2 has been successfully fabricated by the hydrothermal method with 2–10% of Ag3PO4 (X-AT). All the material properties have been investigated using XRD, HR-TEM, FEG-SEM, UV–Vis (DRS), BET surface area, XPS, and PL spectroscopy. The optoelectronic and structural properties have been correlated with materials photocatalytic performance with visible light illumination. XRD implies the formation of anatase and cubic phases of TiO2 and Ag3PO4 nanoparticles, respectively, with average crystallite size in the range of 18–25 nm. The formation of a proper heterojunction is corroborated by HR-TEM image. The addition of Ag3PO4 decreases the band gap from 3.2 for TiO2 to 2.56 eV for 10-AT heterojunction. The photocatalytic reduction of Cr(VI) and deterioration of basic fuchsin were evaluated for the Ag3PO4–TiO2 nano-heterojunction. 50 ppm of Cr(VI) solution is completely reduced into Cr(III) within 75 min of visible light irradiation using 10-AT, whereas the same material takes 120 min for the complete degradation of 10 ppm of basic fuchsin dye solution. Bare TiO2 and Ag3PO4 show insignificant photocatalytic efficiency under similar conditions. The improvement can be attributed to the synergistic effect of diminished charge carrier recombination and increased visible light absorption due to the surface plasmon resonance of the metallic silver nanoparticle and oxygen vacancies. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.