Synergistic effects of bimetallic CuNi–ZrO 2 catalysts in catalytic transfer hydrogenation of furfural

Bimetallic synergy can competently optimize the electronic structure of active metals and coordinate interaction between metal components, which is a good strategy to effectively enhance the catalytic performance and stability of monometallic catalysts. Herein, we report a CuNi bimetallic catalyst supported on mesoporous zirconia prepared via electrospinning technology, which can achieve high catalytic transfer hydrogenation (CTH) performance with excellent cycling stability. The bimetallic synergistic effect on CTH capacity was systematically investigated by precisely regulating the Cu/Ni molar ratio. The optimized Cu₂Ni₁-ZrO₂ catalyst exhibited exceptional performance, achieving 88.9% furfural conversion with 93.6% furfuryl alcohol selectivity in isopropanol at 170 °C for 12 h, accompanied by a notable TOF value of 4.90 h^-1. The electron transfer between Cu and Ni promotes the generation of more Cu⁰/Cu⁺ active sites, which effectively enhances the CTH activity of the catalyst. Additionally, the Cu₂Ni₁-ZrO₂ catalyst showed stable performance over 6 cycles with negligible activity decay. Finally, the hydrogen transfer pathway of furfural on the catalyst surface was studied via H isotope labeling mass experiments.