Ni/graphene Nanostructure and Its Electron-Enhanced Catalytic Action for Hydrogenation Reaction of Nitrophenol

Two-dimensional (2D) heterostructured Ni/graphene nanocomposites were constructed via electrostatic-induced spread by following in situ-reduction growth process for magnetically recyclable catalysis of p -nitrophenol to p -aminophenol. The heterostructures with large 2D surface and moderate inflexibility enable the superior catalytic activity and selectivity toward hydrogenation reaction for p-nitrophenol. On the basis of high-efficiency utilization of Ni Nps catalysis activity and electron-enhanced effect from graphene, the coupling effect of Ni/graphene magnetic nanocomposites can lead to highly catalytic activity for the hydrogenation reaction of p-nitrophenol with the pseudo-first-order rate constants of 11.7 × 10 –3 s –1, which is over 2-fold compared to Ni Nps (5.45 × 10 –3 s –1 ) and higher than reported noble metal nanocomposites. Complete conversion of p -nitrophenol was achieved with selectivity to p -aminophenol as high as 90% under atmosphere and room temperature. Additionally, this heterostructured magnetic nanocatalyst can be efficiently recycled with long lifetime and stability over 10 successive cycles. This work displayed the value of non-noble metal/graphene nanocomposites in catalysts development for green chemistry.