Evaluation of Vanadium Oxide Nanocatalysts over Graphene for Propylene Production Through Oxidative Propane Dehydrogenations

This study reports an efficient and low-cost hydrothermal method for synthesizing vanadium oxide/graphene nanocatalysts. Field-emission scanning electron microscopy (FESEM) revealed the formation of nanostructured catalysts with consistent and directional shapes, as confirmed by X-ray diffraction (XRD). Fourier transform infrared (FTIR) spectroscopy indicated the presence of V2O5 and graphene, highlighting their bonds and structures. Thermogravimetric analysis (TGA) identified three stages of weight loss in the nanocatalysts, corresponding to water molecule evaporation, decomposition of residual organics, and the formation of yellow vanadium pentoxide particles due to the oxidation of vanadium V4+. Gas chromatography analysis from 450 °C to 600 °C showed that ethylene selectivity increased with temperature, while propylene selectivity showed the opposite trend. The effectiveness of these nanocatalysts was assessed in the oxidative dehydrogenation of propane using temperature programmed reduction. The approach of graphene-based vanadium oxide nanostructures will open up a new insight into the fabrication of high-performance catalysts.