On structure and methylene blue degradation activity of an Aurivillius-type photocatalyst of Bi4V2O11 nanoparticles

Aurivillius-type photocatalyst of Bi4V2O11 nanoparticles with an average particle size of 45 nm was prepared by the modified Pechini method. The sample was investigated by X-ray powder diffraction (XRD) and the structural refinement. The nanoparticles were characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopic (XPS) and UV-vis absorption spectrum. Bi4V2O11 nanoparticles show an efficient absorption in the UV-vis light wavelength region with a narrowed band gap energy of 2.08 eV and an indirect allowed electronic transition. The photocatalytic activities of Bi4V2O11 nanoparticles were evaluated by photodegradation of methylene blue (MB) under visible-light irradiation in air atmosphere. These results indicate that Bi4V2O11 could be a potential photocatalyst driven by visible-light. Hybridization of the 6s and 6p orbitals of Bi3+ and the resulting lone electron pair yields interesting properties. The effective photocatalytic activity was discussed on the base of the crystal structure characteristic such as polar (VO3.5□0.5)2− anionic groups, Aurivillius-type (Bi2O2)2+ layers and long distance of the nearest V-V in the lattices, etc.