Au/Ni/Ni(OH) 2 /C Nanocatalyst with High Catalytic Activity and Selectivity for m-dinitrobenzene Hydrogenation

The Au/Ni/Ni(OH)2/C bimetallic nanocatalysts with different Au loadings (Au/Ni/Ni(OH)2/C-1: 0.05 wt%Au; Au/Ni/Ni(OH)2/C-2: 0.46 wt%Au; Au/Ni/Ni(OH)2/C-3: 2.60 wt%Au) were prepared at room temperature. The characterization results proved the nanostructure of Au islands supported on the Ni/Ni(OH)2 nanoparticles (NPs) and synergy effect of Au-, Ni- and Ni(OH)2-related species in Au/Ni/Ni(OH)2/C. These are the main reasons why their catalytic performance and selectivity to m-nitroaniline in m-dinitrobenzene hydrogenation were much higher than those of monometallic catalysts (Au/C and Ni/Ni(OH)2/C). Because Au/Ni/Ni(OH)2/C-2 was with high dispersion of Au, Au(0)/Aun+ ratio≈1:1 on the surface, novel nanostructure, moderate capacity of activating and dissociating hydrogen, and synergistic effect, it had much better catalytic activity (conversion of m-dinitrobenzene-100%) and higher selectivity to m-nitroaniline (95.0%) in m-dinitrobenzene hydrogenation reaction compared to other two supported bimetallic catalysts (Au/Ni/Ni(OH)2/C-1 and Au/Ni/Ni(OH)2/C-3). Au/Ni/Ni(OH)2/C-2 also exhibited high stability.