Highly-dispersed surface NiO species and exposed Ni (200) facets facilitating activation of furan ring for high-efficiency total hydrogenation of furfural

Selective hydrogenation of biomass is indispensable to obtain high value-added chemicals. Herein, carbon-embedded Ni-based catalyst Ni/C-400 was prepared by employing a 3D flower-like MOF Ni-BDC as the sacrificial template. It featured highly exposed Ni (200) facets with abundant highly-dispersed surface NiO species, exhibited an outstanding catalytic performance toward the total hydrogenation of furfural (FFR), and achieved an exceptional tetrahydrofurfuryl alcohol (THFA) yield of 98.5 % under 80 °C and 1 MPa H2. FFR/FFA-temperature program desorption (TPD) was designed for the first time to identify the adsorption capacity and strength between reactants and catalysts. Density functional theory (DFT) calculations confirmed that Ni particles with surface NiO species have a more substantial capacity to adsorb reactants, while the Ni (200) facets are capable of adsorbing more dissociated H atoms, which is the key to concurrently achieving high FFR conversion and THFA selectivity.