Cobalt doping induced electronic effects boosts the hydrogenation of phenol to cyclohexanone.

The hydrogenation of phenolic compounds to achieve high value-added conversion is an important reaction in industrial applications. Promoting the hydrogenation process by regulating the properties of H active species has great potential. In this paper, we achieved in-situ metal doping using the one-pot hydrothermal strategy to regulate the cleavage pathway of H2 on the surface of noble metals, thereby promoting the hydrogenation of phenol to form ketones. The results of catalytic performance, characterization and density functional theory (DFT) calculations confirmed that the Co doping regulated the surface properties of Pd metal, leading to easier heterolytic cleavage of H2 to form electron-rich highly active Hδ- species. Mechanistic studies showed that the modified metal surface was more favorable for the adsorption and activation of H2, and the electron-rich Hδ- species could lower the hydrogenation barrier and promote the progress of the hydrogenation process. In addition, this strategy achieved the highly stable materials with core-shell via one-step synthesis, which showed good stability in continuous use. Our study presents a successful paradigm in biomass conversion, deepening the understanding of the regulation of hydrogenation processes.