Dual-metal synergy unlocking ROS-free catalysis for rapid aerobic oxidation of 5-hydroxymethylfurfural at room temperature

Abstract

Clean catalytic oxidation has a broad prospect in the modern chemical engineering and energy chemistry fields. However, unexpected over-oxidation and disruptive degradation are frequently induced by excessive reactive oxygen species (ROS). Herein, we reported a new ROS-free approach to effectively drive O₂ to be activated into highly reactive surface peroxo species through enzyme-mimicking mechanism. Benefiting from the dual-metal synergy effect between Cu and Co active sites, ROS (H₂O₂ and OH^•) is generated in situ while further scavenged completely into surface peroxo species, which gives rise to very high selectivity and extremely high carbon balance. For example, the CuCo/N-C catalyst affords >99.8% conversion and 94.5% selectivity to 2,5-furanedicarboxylic acid at 25 °C for 6 h in the aerobic oxidation of biomass platform 5-hydroxymethylfurfural. Moreover, it achieved exceptional performance in the oxidation of a variety of hydroxyl compounds to organic acids with high yields (89.9%–99.5%) at a mild temperature (25–40 °C). This exploration introduces an innovative clue for emulating enzyme catalysts, thereby enriching our comprehension and advancement of biologically inspired catalytic oxidations.