Engineering the electronic structure of Pt for selective hydrogenation of vanillin to vanillyl alcohol and p-cresol

The hydrogenation of vanillin stands as a pivotal platform reaction within biomass conversion processes, presenting a significant challenge in achieving controlled synthesis of different products. Here, we proffer different methodology for elaborately designing the electronic structure of Pt via regulating the strong metal-support interactions (SMSI) between Pt and Mo 2 TiC 2 , thereby facilitating the targeted synthesis of vanillyl alcohol (VA) and 2-methoxy-4-methylphenol (MMP) from vanillin. Appropriate H 2 reduction can enhance the SMSI between Pt and Mo 2 TiC 2 , promoting the electron transfer from Mo 2 TiC 2 to Pt, resulting in 200-Pt/Mo 2 TiC 2 with 68.1 of Pt 2+ . However, the SR-Pt/Mo 2 TiC 2 obtained through the galvanic replacement strategy possesses 64.7 % of Pt 4+ , which is attributed to the weaker spontaneous SMSI between Pt and Mo 2 TiC 2 . XPS adsorption experiments highlight the pivotal role of Pt 2+ in facilitating the desorption of VA, resulting in the 200-Pt/Mo 2 TiC 2 catalyst demonstrating exceptional selectivity towards VA (96 %). Meanwhile, SR-Pt/Mo 2 TiC 2 showcases a predilection for the direct hydrogenation and deoxygenation of vanillin into MMP. This research not only marks the application of the MXene system to biomass conversion but also illuminates the relationship between the electronic structure of Pt and its selectivity towards VA and MMP.