3D-interconnected hierarchical porous N-doped carbon supported ruthenium nanoparticles as an efficient catalyst for toluene and quinoline hydrogenation
Ruthenium nanoparticles (2.6 nm) uniformly dispersed on a three-dimensional (3D) interconnected hierarchical porous N-doped carbon (Ru/NHPC) have been successfully developed, serving as a highly active and stable catalyst for the selective hydrogenation of aromatics under mild conditions. A novel “leavening” strategy, i.e. using biomass-derived α-cellulose as a carbon precursor and ammonium oxalate as both a nitrogen source and foaming agent, affords the NHPC material a large surface area (870 m2 g−1), an excellent hierarchical nanostructure which acts as a convenient mass transfer channel and a high ability in stabilizing and dispersing Ru nanoparticles. The Ru/NHPC catalyst exhibits a substantially enhanced activity for the hydrogenation of toluene (TOF up to 39000 h−1) and quinoline (TOF up to 2858 h−1) in comparison with Ru/HPC (3D-hierarchical porous carbon without nitrogen doping) and Ru/AC (commercial activated carbon) under the same reaction conditions. Further investigations indicate that the 3D interconnected porous structure and N-doping contribute to the improved diffusion and mass transfer, homogeneous dispersion of ruthenium nanoparticles and high percentage of Ru0 (active sites), which results in considerable catalytic performance. This work offers great potential for the application of supported catalysts based on NHPC materials in fine chemical production with high activity.