Insights into the catalytic mechanism of V-Mo@CN for the oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran

The efficient synthesis of 2, 5-diformylfuran (DFF) over non-noble metal catalysts has been a significant challenge in biomass conversion strategies. Herein, a bimetallic V-Mo oxide supported by nitrogen-doped carbon (VMo@CN) was fabricated for the efficient oxygenation of 5-hydroxymethylfurfural (HMF) towards DFF. Remarkably, under the optimal conditions, a full conversion of HMF was achieved with an impressive DFF yield of 97.1 %. This oxidation reaction was determined to be a first-order reaction with a relatively lower apparent activation energy of 46.76 kJ/mol and proceeded by the synergistic redoxes of V5+/V3+ and Mo6+/Mo4+ with the assistance of the highly mobile lattice oxygen. The synergism of the V-species, Mo-species and @CN support contributed to the high-efficiency oxidation of HMF to generate DFF. The synergistic action of the V-species and O-species was responsible for the competitive adsorption advantage of the C-OH in HMF with a vertical configuration, ensuring the highly selective and efficiency in oxidizing HMF toward DFF.