Structural control of V2O5 nanoparticles via a thermal decomposition method for prospective photocatalytic applications

Abstract

BackgroundRecently, transition-metal oxides have represented an exciting research topic, especially their fundamental and technological aspects. Here, vanadium pentoxide nanoparticles (V2O5-NPs) were synthesized through the thermal decomposition of ammonium meta-vanadate. In the current study, we investigated the photocatalytic activity of V2O5-NPs to develop and regulate the V2O5 structure for adsorption applications.ResultsThe obtained nanoparticles were inspected by X-ray diffraction, scanning electron microscope, transmission electron microscope, and differential thermogravimetric analysis, which proved the formation of the nanorod structure. The ultraviolet–visible absorption spectra revealed a 2.26 eV band gap for V2O5-NPs that correlates with indirect optical transitions. The photocatalytic activity of the V2O5-NPs was investigated by methylene blue (MB) degradation in aqueous solutions. An initial concentration of 25 ppm, a temperature of 40 °C, 40 mg of adsorbent mass, and 1 h of contact time were the optimal conditions for the efficient removal of MB that could reach up to 92.4%. The mechanism of MB photocatalytic degradation by V2O5-NPs is explained.ConclusionsThe photodegradation data better fit with the Langmuir isotherm model. The thermodynamic parameters indicated that the adsorption was spontaneous and endothermic. The reaction kinetics followed the pseudo-second-order model. Thermally prepared V2O5-NPs offer a simple and efficient approach for selective MB removal from an aqueous medium.Graphical abstract