Visible–light photocatalytic activities of ?VO3 nanorods and BiVO4 nanobars

Monoclinic ?–AgVO3 nanorods (thickness 30 nm) and monoclinic BiVO4 nanobars (thickness 15 nm) with high aspect ratio are prepared by controlling the reaction kinetics of room temperature precipitation, without using any capping agents or surfactants. The nanocrystalline vanadates are characterised using XRD, SEM, EDAX, FESEM, TEM and AFM. Possible growth mechanisms of the nanocrystals are explained by the oriented attachment of flocs through an anisotropic growth. Ag nanoparticles are formed in–situ on AgVO3 nanorods. Using diffuse reflectance spectral analysis the band gaps of ?–AgVO3 nanorods and BiVO4 nanobars are calculated and their photocatalytic behaviour is investigated by photodegradation of methylene blue. The ?–AgVO3 nanorods have higher pore volume compared to BiVO4 nanobars. The Ag nanoparticles attached on the surface of AgVO3 nanorods serve as active sites for photocatalysis. Hence silver vanadate nanorods exhibit remarkably enhanced photocatalytic activity and are a good candidate for visible light driven photocatalyst.