Ni nanoparticles decorated Ni–N–C catalyst: Dual-site synergy for enhanced catalytic hydrogenation

Abstract

It is highly desired but still challenging to engineer single-atom catalysts featuring an M–N–C configuration for efficient catalytic hydrogenation. Herein, Ni nanoparticles (Ni NPs) modified Ni–N–C (termed as Ni_1+NPs/NSPC) were fabricated to demonstrate the feasibility of enhancing the catalytic hydrogenation performance of M–N–C by introducing metallic NPs sites. Ni_NPs sites and Ni₁ sites displayed a synergistic effect: Ni_NPs promote the dissociation of H₂ in a homolytic manner with a lower barrier energy than the heterolytic one that occurred on Ni₁ sites, whereas Ni₁ could burden the activation of substrates. The active H atoms generated at Ni_NPs migrate to Ni₁ sites to complete hydrogenation. Consequently, Ni_1+NPs/NSPC catalysts were empowered with excellent hydrogenation performance; they can be applied to a series of hydrogenation substrates (e.g., nitro compounds, furfural, quinine, and cyanophenyl) affording high conversion (95.1%–99.9%) and selectivity (96.8%–99.9%).