Regulating the Electronic State of Ruthenium via a Support Facet Structure for the Efficient Selective Hydrogenation of Benzene

Ruthenium-based catalysts have attracted considerable attention owing to their excellent activity in the selective hydrogenation of benzene to cyclohexene. Their catalytic performance is primarily governed by the electronic structure of metallic active sites and the interfacial interaction between the metal and the support. In this work, three types of TiO2support, including nanosheet flowers (TNSFs), elongated bipyramids (TNEBs), and tetragonal bipyramids (TNQBs), were successfully synthesized via a solvothermal route, which predominantly expose the (001), (010), and (101) crystal facets, respectively. Subsequently, ruthenium nanoparticles were deposited onto the support surfaces by means of chemical reduction, yielding three supported catalysts. The exposed (101) crystal facets of TNQBs induce the strongest electronic metal–support interaction (EMSI). Abundant Ti3+defects and oxygen-containing species on the surface endow the catalyst with superior hydrophilicity, enhancing the contact between the reaction medium and active sites as well as the desorption of cyclohexene. Meanwhile, the supported Ru species exhibit the highest fraction of electron-deficient states, with the proportion of Ruβreaching up to 82.22%. As a result, the catalyst exhibits outstanding catalytic performance, achieving a benzene conversion of 42.8%, a cyclohexene selectivity of 82.27%, and a cyclohexene yield as high as 53.22%.