Rhodium nanoparticles in ZrO2 on N-doped carbon leads to ultra-high catalytic selectivity and activity in nitroarene hydrogenation

Metal nanoparticles are widely considered for heterogeneous catalysis due to their high atomic efficiency and tunable active microenvironment, but their specific functional tendencies are still unclear. Here, we report that a Rh@ZrO 2 /NC catalyst with only 0.1 wt% Rh exhibits exceptional catalytic performance and high selectivity (p-nitroacetophenone conversion-98.6 %, p-aminoacetophenone selectivity-100 %, r -56.4 mol p-nitroacetophenone /(mol Rh ·min)) towards the hydrogenation of the -NO 2 group in nitroarene to -NH 2 . This is because the interaction between Rh species and “ZrO 2 -N” results in significant hydrogen spillover in the catalyst, as supported by DFT calculations. Extensive characterizations from TG, DTG, NAP-XPS, in-situ Raman spectroscopy, in-situ DRIFT spectroscopy and DFT calculations further confirm the adsorption, activation and dissociation of hydrogen on Rh nanoparticles. The H* species migrate readily over ZrO 2 -NC, to facilitate the catalytic activity and selectivity for the hydrogenation of nitroarene. This study presents a new approach to develop highly efficient and selective metal nanoparticle-catalysts for cost-effective hydrogenation reactions. • A highly dispersed Rh@ZrO 2 /NC catalyst is synthesized in one pot. • Synergism and hydrogen-spillover among Rh, ZrO 2 and NC play key roles in catalysis. • The catalyst enhances H 2 adsorption and reduces the energy barrier for hydrogen spillover. • The catalyst exhibits excellent activity and selectivity for nitroarene hydrogenation.