NiZr/N‐doped TiO2/Ti3C2 catalyst for the selective hydrogenation of cinnamaldehyde: effect of N‐doping of TiO2

Abstract

AbstractAn NiZr/N‐doped TiO2/Ti3C2 catalyst was prepared by KBH4 reduction for cinnamaldehyde hydrogenation. Characterization results showed that the synthesis of N‐doped TiO2 on Ti3C2 and the uniform dispersion of TiO2 on the Ti3C2 surface increased the specific surface area of NiZr/Ti3C2 by 164.4 m2/g. N‐doping at a level of 19.03 % was used to replace O in the TiO2 lattice; the Ti−O−Ti peak in the XPS spectrum of the undoped catalyst was shifted by 0.3 eV in the spectrum of the doped catalyst; as a result, there was a 15.40 % increase in the number of surface oxygen vacancies of the NiZr/Ti3C2 catalyst. The synthesis of N‐doped TiO2 on Ti3C2 converted the moderately acidic sites of NiZr/Ti3C2 to strong Lewis acid sites and increased the total number of acid sites by approximately 0.8‐fold. The active Lewis acid sites on the surface of NiZr/N‐doped TiO2/Ti3C2 adsorbed only C=O bonds and inhibited the adsorption of C=C bonds, resulting in a high cinnamaldehyde conversion of 90.69 % and a cinnamyl alcohol selectivity of 91.87 %.