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.