Photocatalytic Selective Oxidation of 5-Hydroxymethylfurfural to 2,5-Diformylfuran over Nb2O5 under Visible Light

The photocatalytic selective oxidation of biomass derivate compound 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran is an environmentally friendly and energy-saving process. Nb2O5 was prepared and applied in the oxidation of HMF under visible light, although its bandgap energy is higher than 3.2 eV. The reaction process follows a special mechanism over a Nb2O5 catalyst different from the normal oxide semiconductor. The effect of calcination temperature, incident wavelength, and reaction time on photocatalytic performance was investigated. Nb2O5-800 exhibits the best performance in the presence of O2 with benzotrifluoride as a solvent under visible light irradiation.