Synthesis and application of V2O5-CeO2 nanocomposite catalyst for enhanced degradation of methylene blue under visible light illumination.

Methylene blue dye is among the toxic, mutagenic, and carcinogenic pollutants. Hence, its treatment via photocatalytic degradation is an important remediation method for the sake of a healthy environment. Herein, the V2O5-CeO2 nanocomposite catalysts were synthesized via a simple precipitation-thermal decomposition approach and used for the photodegradation of methylene blue in the presence of H2O2 as an effective electron scavenger under visible light illumination. The nanocomposite catalysts were systematically characterized to investigate the effects of V2O5 with the aids of X-ray, morphology, light absorption, catalytic activity, and charge transfer properties of the nanocomposite catalysts. The VC-2 nanocomposite prepared with NH4VO3:CeO2 molar ratios at 0.15:1 was found to be the best efficient catalyst where ≥98% of methylene blue was degraded within 25 min irradiation time. From the kinetics analysis, its rate constant was found to be higher than those of the pure V2O5 and CeO2 catalysts by a factor of 12.0 and 13.5, respectively. The plausibly mechanistic elucidation of charge transfer and utilization of reactive species are conspicuous allegations of the combined effects of the nanocomposite catalyst, H2O2 sacrificial agent, and visible light for the photodegradation of the dye.