Nanocarbon catalysts with co-active S–P–C sites enhance metal-free direct oxidation of alcohols

Abstract

In this study, a sulfur–phosphorus co-doped nanocarbon (SPC) catalyst was synthesized using a straightforward one-step colloidal carbonization method and demonstrated high performance in the metal-free direct oxidation of alcohols to aldehydes. This metal-free SPC catalyst showed exceptional efficiency, achieving a conversion rate of 90% for benzyl alcohol and a selectivity of 94% toward benzaldehyde within only 1 h at 130°C. Moreover, it displays exceptional cycle stability and a high turnover frequency (17.1 × 10^–3 mol g^–1 h^–1). Theoretical analysis suggested that the catalyst’s superior performance is attributed to the presence of unsaturated edge defects and S–P– moieties, which increase the density of states at the Fermi level, lower the band gap energy, and promote electron localization. Additionally, the doping introduces cooperative co-active S–P–C sites, facilitating a synergistic multisite catalytic effect that lowers the energy barriers. These findings represent a significant advancement in the field of metal-free direct alcohol oxidation.

Keywords

alcohol oxidation reaction / carbon / catalysts / electronic structures

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