The synergy of Co-MoN-MgO on 2D carbon sheets for effective catalytic hydrogenation

Abstract

The Co-based materials are the promising catalysts for the catalytic hydrogenation reactions. The optimization of the electronic structure and micro-morphology to achieve like-noble-metal catalysis is a current research hotspot. Here, the Co-MoN-MgO heterojunctions embedded on 2D carbon nanosheets (Co-MoN-MgO/C) were designed in a melt-salt system for efficient catalytic hydrogenation of the nitro-compounds. The tests show the intimate contact of Co with MoN, realizing effective synergy for promoting the electrons transfer from Co to MoN. The transfer optimizes the electronic structure of Co components, being favorable for the adsorption/desorption of intermediates and catalytic hydrogenation reaction. The 2D porous structure gives enhanced mass-transfer ability and large accessible surface for better contact with the reactants. Above features endow Co-MoN-MgO/C with good catalytic activity for p-nitrophenol (4-NP) hydrogenation, with a reaction rate constant k of 0.41 min−1 (10 °C), which is 2.73 times greater than Co-MgO/C catalyst (0.15 min−1) and even better than some reported noble-metal catalysts. Furthermore, the catalyst shows good cycling stability with no obvious deactivation after 10 cycles and obvious catalytic activity for a series of nitro-compounds. This work has important implications for the design of efficient non-noble-metal synergistic catalyst for the effective catalytic hydrogenation.