Efficient and selective oxidation of furfural into high‐value chemicals by cobalt and nitrogen co‐doped carbon

Abstract Supported non‐noble metal catalysts for the selective oxidation of furfural into high‐value chemicals have attracted considerable attention. Herein, an atom‐level‐isolated, cobalt‐catalyst‐supported N‐doped carbon (Co SAs‐N@C) was synthesized through a metal cobalt–tannic acid coordination assembly strategy. The obtained Co SAs‐N@C with 7.68 wt% of Co content was qualitatively and quantitatively characterized by X‐ray diffraction, X‐ray photoelectron spectroscopy, high‐resolution transmission electron microscopy, high‐angle annular dark‐field scanning transmission electron microscopy, inductively coupled plasma optical emission spectrometer, and X‐ray absorption fine structure techniques. From the structural properties, potassium thiocyanate poisoning, and acid leaching, it was found that the atomic‐dispersed CoNx species of the catalyst acts as the active site and plays a vital role in its highly effective oxidative esterification activity. The catalytic mechanism of this reaction is involved in radical oxidation, as confirmed by electron paramagnetic resonance spectra. The density functional theory calculations revealed that the reaction pathway proceeds as a hemiacetal pathway. Interestingly, the Co SAs‐N@C catalyst also showed satisfactory catalytic activity for the aerobic oxidation of furfural. Unexpectedly, the Co SAs‐N@C catalyst still possessed excellent stability and recyclability without loss of activity after five reuses.