Rapid synthesis of doped-ceria catalysts via carbon-mediated microwave combustion for boosting oxidative coupling of alcohols and amines

The oxidative coupling of alcohols and amines to imines represents a green and atom-economical route for C=N bond formation. Nevertheless, the rapid and efficient synthesis of high-performance oxide catalysts for this transformation remains a significant challenge. Herein, we report a novel carbon nanotube-mediated, microwave-assisted solution combustion method for the fabrication of manganese-doped ceria catalysts. The optimized Ce 7 Mn 3 O δ -20CN catalyst exhibits exceptional performance in oxidative coupling of alcohols and amines, achieving 95% conversion of benzyl alcohol and 99% selectivity toward the corresponding imine, along with enhanced recyclability. Comprehensive characterization reveals that Mn incorporation effectively suppresses crystallite growth and significantly enhances oxygen vacancy concentration compared to pure CeO 2 . More importantly, the multiple interaction effect between carbon nanotubes and microwave fields not only amplifies these structural and electronic advantages but also strengthens Ce-Mn interactions. Furthermore, this catalyst also demonstrates broad substrate tolerance across diverse alcohols and amines. Notably, this carbon-mediated microwave combustion synthesis strategy has been successfully extended to the synthesis of Zr-, Co-, Ni-, Fe-, and Al-doped ceria catalysts. This work offers a versatile and robust platform for the rapid synthesis of high-performance doped ceria-based materials tailored for sustainable oxidation catalysis.