Phytic acid-assisted phase-controlled synthesis of nickel phosphides for highly selective hydrogenation of biomass-derived furfural

Developing cost-effective and highly active catalysts for the selective hydrogenation of furfural to target products is significant yet remains a substantial conundrum in the chemical industry. Herein, we present a phytic acid-assisting pyrolysis strategy to phase-controlled synthesis of a series of nickel phosphides catalysts (Ni 3 P/mSiO 2 , Ni 12 P 5 /mSiO 2 and Ni 2 P/mSiO 2 ), which exhibited phase-dependent catalytic performance in furfural hydrogenation. Ni 12 P 5 /mSiO 2 achieved the highest yield (97.3 %) of cyclopentanone under 1 MPa H 2 at 150 °C, and Ni 3 P/mSiO 2 could further hydrogenate cyclopentanone to a 60.8 % yield of cyclopentanol when the H 2 pressure increased to 2 MPa. Meanwhile, Ni 2 P/mSiO 2 demonstrated temperature-controlled selectivity for switching between furfuryl alcohol and cyclopentanone. Detailed characterizations and density functional theory calculations elucidated that the differences in catalytic performance were primarily attributed to the hydrogenation ability and acidity of catalysts as well as furfural adsorption configuration, which were determined by the tunable crystal phases of nickel phosphides. This work paves the promising avenue for the rational design of metal phosphide catalysts and harnessing their considerable potential for biomass conversion.