Effective Photocatalytic Degradation of Methyl Orange Using V2O5@ZnO Nanocomposite under UV and Visible Irradiations

Abstract

Today, reclamation and reuse of wastewater from textile, food and pharmaceutical industries are the big challenges for researchers to decrease the diseases and pollution in the world. Thus, this study was conducted for the design of V2O5@ZnO nanocomposite and its application as a photocatalyst for degradation of methyl orange under UV and visible irradiations. The V2O5@ZnO nanocomposite was synthesized with a homogeneous combination of hydrothermal synthesized ZnO nanorods and V2O5 nanoparticles. The morphological, structural, optical, electrochemical and photocatalytic degradation characterizations of prepared nanocomposite and its components were studied. Optical result showed the red shift in edge of absorption spectra of V2O5@ZnO nanocomposite toward the ZnO nanorods film which indicate the transferring enhancement of photo-generated carriers between two-components of nanocomposites. It can decrease the recombination rate of photo-excited charges due to interface effect through creation of the separation channel of electrons and holes. Electrochemical impedance spectroscopy analysis displayed lower charge transfer resistance and effective separation of photo-excited charges on V2O5@ZnO nanocomposite surface under visible light irradiation. Photocatalytic measurements showed 60% enhancement in the degradation efficiency for V2O5@ZnO nanocomposite under 3 hours irradiation of visible light toward the UV light. It can be attributed to the high effective surface area of homogeneously combining V2O5 nanoparticles and ZnO nanorods and narrowing the band gap of prepared nanocomposite toward the ZnO film. Furthermore, this finding showed the stable activity for degradation of methyl orange on the V2O5@ZnO nanocomposite film surface. These results indicate that the prepared V2O5@ZnO nanocomposite can be applied for high efficiency degradation of methyl orange under irradiation of visible light.