화학공학소재연구정보센터
Journal of Catalysis, Vol.382, 97-108, 2020
Promoting the performances of Ru on hierarchical TiO2 nanospheres exposed {001} facets in benzene semi-hydrogenation by manipulating the metal-support interfaces
We devised ruthenium-based catalysts with hierarchical anatase TiO2 nanospheres (HATNs) constructed by ultrathin nanosheets (NSs) exposed different degrees of {0 0 1) facets as the supports for semi hydrogenation of benzene (SHB) and boosted the performances by manipulating the metal-support interfaces (MSIs). With the aid of systematic characterizations, it is identified that appropriately prolonging the solvothermal time gave rise to an enhancement in TiO2 crystallinity and an increment in exposed degree of {0 0 1) facets. As a result, the amounts of acid sites and coordinatively unsaturated (cus) fivefold-coordinated Ti (Ti-5c) atoms on the Ru/HATN5 catalysts were increased. The former aroused an enhancement in turnover frequency (TOF) of benzene by providing additional hydrogenation on the acid sites, and the latter boosted the cyclohexene selectivity. The initial selectivity and yield attained to 83% and 51%, respectively, on the Ru/HATNs-24 catalyst exposed the most {0 0 1) facets. Kinetics analysis and temperature-programmed desorption (TPD) of cyclohexene demonstrated that the cus Ti-5c atoms on the {0 01) facets can accelerate the rate of benzene hydrogenation more than that of cyclohexene hydrogenation, decrease the adsorption site and capacity of cyclohexene, and weaken the adsorption strength of cyclohexene, which are responsible for the selectivity enhancement. (C) 2019 Elsevier Inc. All rights reserved.