Direct sunlight-driven enhanced photocatalytic performance of VO nanorods/ graphene oxide nanocomposites for the degradation of Victoria blue dye.

Herein, we report the synthesis and characterizations of Vanadium pentoxide (VO) nanorods/graphene oxide (GO) nanocomposite as efficient direct solar light driven photocatalyst for the enhanced degradation of victoria blue (VB) dye. The nanocomposite was synthesized by sonochemical process and characterized using several analytical methods in order to study the structural, morphological, compositional, optical and photocatalytic properties. The X-ray diffraction studies confirmed the orthorhombic structure of VO while the morphological examinations revealed the growth of VO nanorods and 2D GO sheets. Interestingly, the UV studies ratify that the bandgap of the nanocomposite was reduced compared to pure GO and VO. Interestingly, the interaction of the VO nanorods with the graphene oxide substrate and its effect on the electronic properties of the combined system, have been examined by means of theoretical calculations, based on the so called Geometry, Frequency, Noncovalent, eXtended Tight Binding (GFN-xTB) method. Studying the photocatalytic behavior of nanocomposite, we observe an almost complete degradation (97.95%) of Victoria Blue (VB) dye under direct sunlight illumination within just 90 min. The outstanding nanocomposite photocatalytic efficiency was due to the excellent transfer of interfacial charge and the suppressed recombination of charge-carrier. The kinetics of the degradation process was also analyzed by calculating the rate constant and half-life time. Finally, a possible mechanism has also been discussed for the degradation process of VB dye using nanocomposite under direct sunlight irradiation.