Abstract

The development of sustainable catalytic systems for biomass valorization is of great importance in the transition toward renewable energy and green chemical processes. In this study, a noble-metal-free Bi₂O₃-Cr₂O₃ catalyst supported on nitrogen-doped carbon nanotubes (N-CNT) was developed for the aerobic conversion of carbohydrates into 2,5-diformylfuran (DFF) using molecular oxygen as the oxidant. The catalytic system enables a direct one-pot transformation of fructose and sucrose to DFF without intermediate isolation, achieving yields of 68.2% and 51.6%, respectively, under optimized conditions (160 °C, 12 h, O₂ atmosphere). The enhanced catalytic performance is attributed to the synergistic interaction between Bi₂O₃ and Cr₂O₃, which promotes oxygen activation and selective oxidation, while the N-CNT support improves dispersion and electron transfer. Compared to conventional systems relying on noble metals or stoichiometric oxidants, this approach offers a more sustainable and cost-effective pathway for biomass upgrading. The combination of non-noble metal composition, aerobic oxidation, and process simplification highlights the potential of this catalytic system for the production of renewable platform chemicals and energy-related materials.

Graphical abstract