Dually functional NiSi intermetallic compounds for the efficient hydrogenation and oxidation of cinnamaldehyde

Intermetallic compounds (IMCs) are promising catalysts for upgrading biomass-derived platform chemicals. Herein, bifunctional NiSi IMCs catalysts were developed for the hydrogenation and oxidation of cinnamaldehyde (CAL). A solvent-free arc-melting method was employed for the synthesis of NiSi IMCs within 5 min. The NiSi IMCs catalysts afforded 99 % conversion of CAL and presented ∼ 71 % yield of 2-phenyl propanol and ∼ 34 % yield of benzaldehyde for the hydrogenation and base-free oxidation of CAL, respectively. Moreover, NiSi IMCs could be used for five runs without deactivation. Characterizations and theoretical calculation results indicated the formation of intermetallic structure and the existence of Si vacancy sites, which could not only facilitate the efficient hydrogenation of CAL but also expose NiOx species as catalytic centers for the oxidation of CAL, leading to the high performance and stability in both hydrogenation and oxidation process.