Interfacial synergy between atomically dispersed Co and encapsulated Co nanoparticles on carbon-based catalyst for efficient hydrogenation of nitroaromatics

Non-noble metal-based catalysts are highly desired for the catalytic hydrogenation of nitroaromatics. Here we reported a catalyst of Co₁/Co_n@NCNS prepared with raw materials for efficient hydrogenation of nitrobenzene (NB), in which the Co nanoparticle (Co_NP) was tightly coated in a nitrogen-doped graphite carbon shell, and the Co single atom (Co_SA) was uniformly anchored on graphite support. The catalyst achieved a conversion of NB for over 99 % under mild conditions at 50 °C and 10 bar. The catalyst was able to consistently maintain over 90 % conversion and 99 % selectivity for 100 h, and exhibited outstanding catalytic activity and selectivity (>99 %) towards the reduction of various nitroaromatics, even though for halogen-containing substrates. The superior catalytic performance resulted from the synergy between the internal Co _NP and the surface Co_SA on the nitrogen-doped carbon shells. Both Co_NP and Co_SA synergistically facilitated electron transfer to nitrogen atoms in the carbon framework, and rendered them catalytic activity during the hydrogenation.