MIL-47(V)-derived carbon-doped vanadium oxide for selective oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran.

ABSTRACT

The development and transformation of biomass-derived platform compounds is a sustainable way to deal with the fossil fuel crisis. 5-Hydroxymethylfurfural (HMF) can be reduced or oxidized to produce many high-value compounds; however, it is challenging to effectively produce 2,5-diformylfuran (DFF) due to overoxidation. In this work, a carbon-doped V2O5 (C-V2O5) material was obtained through pyrolysis of MIL-47(V) nanorods, a typical metal-organic framework material. The X-ray diffraction patterns and X-ray photoelectron spectra showed that the graphitized carbon species were incorporated in C-V2O5. High-efficiency HMF oxidation, high specific selectivity for DFF and excellent recycling could be achieved with the C-V2O5 catalyst. Fourier-transform infrared spectroscopy combined with density functional theory (DFT) calculation revealed that graphitized carbon weakens the VO bond and promotes the formation of oxygen vacancies in C-V2O5, thus improving the catalytic activity in the oxidation of furfuryl alcohols. The V4+ induced by oxygen vacancies will be oxidized by O2 to form V5+, so that the cycle can be realized. It exhibits remarkable selectivity in the oxidation of different alcohols produced from biomass based on the relatively constant active sites in C-V2O5.