Precision Hydrogenation of Acetophenone to Phenylethanol over Pd 1 -(CuO x ) 1 Hybrid Nanoparticles Confined in KIT-6 Channels

Modifying noble metal catalysts with transition metal oxides (MO x ) is an effective strategy to enhance both catalytic activity and selectivity through interfacial synergy. However, achieving precise spatial colocalization of the metal and oxide phases remains a challenge. Herein, Pd 1 -(CuO x ) 1 hybrid nanostructures confined within KIT-6 mesoporous silica were rationally synthesized via in situ oxidative transformation of PdCu bimetallic nanoparticles (NPs) under controlled thermal treatment. The resulting Pd 1 -(CuO x ) 1 /KIT-6 catalysts exhibited markedly enhanced activity and chemoselectivity for the hydrogenation of acetophenone to 1-phenylethanol compared with monometallic Pd/KIT-6 and PdCu/KIT-6. The optimal catalyst with a Pd/Cu molar ratio of 1:1 achieved 93.1% acetophenone conversion and 98.2% selectivity toward 1-phenylethanol, and demonstrated broad applicability across a range of ketone substrates. Comprehensive structural characterization revealed that the Pd-CuO x interfacial sites are central to the observed performance enhancement: metallic Pd facilitates H 2 dissociation, while adjacent CuO x species are proposed to facilitate carbonyl adsorption, contributing to the overall synergistic enhancement. This interface-driven synergistic mechanism provides a general, efficient, and cost-effective strategy for the selective hydrogenation of multifunctional molecules.