Yolk-Shell type Carbon-Silica Nanoarchitecture Dispersed and Stabilized Ru Nanoparticles for Enhanced Hydrogenation of Aromatic Compounds

Hydrogenation of aromatic rings can be used not only for synthesis fine chemicals, but also for hydrogen storage and transportation using organic hydride. In this paper, yolk-shell structural SiO2@Ru@NC catalyst, which was successfully synthesized by a strategy of combining modified Stöber and vacuum-assisted impregnation, revealed excellent catalytic activity in dimethyl terephthalate (DMT) hydrogenation to dimethyl 1,4-cyclohexanedicarboxylate (DMCD), which is a green chemical reagent and precursor for high-value chemicals. Characterization results showed that highly dispersed Ru NPs with subnanometer size distribution were encapsulated in yolk-shell nanoarchitecture and the mesoporous shell could ensure unhindered diffusion of reactant molecules. Moreover, yolk-shell structure-induced interaction of Ru and carbon shell allowed for tuning electronic structure of Ru species, which in turn could regulate catalytic properties. The yolk-shell nanoarchitecture catalyst offers advantages of low active metal loading, excellent activity and stability, thus can expand application of ultra-low loaded precious metal catalysts in catalytic conversion of aromatic compounds.