Promoting the performances of Ru on hierarchical TiO2 nanospheres exposed {001} facets in benzene semi-hydrogenation by manipulating the metal-support interfaces
Promoting the performances of Ru on hierarchical TiO2 nanospheres exposed {001} facets in benzene semi-hydrogenation by manipulating the metal-support interfaces
复制标题
通过操纵金属-载体界面提高苯半氢化中暴露{001}面的分层TiO2纳米球上Ru的性能
DOI：
10.1016/j.jcat.2019.12.017
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发表时间：
2020
影响因子：
7.3
通讯作者：
Gongbing Zhou
中科院分区：
文献类型：
--
作者：
Lan Jiang;Gongbing Zhou
本文设计了一种钌基催化剂，由不同程度的{0 0 1}面暴露的超薄纳米片（NSs）构建层状锐钛矿tio2纳米球（HATNs）作为苯半加氢（SHB）的载体，并通过操纵金属支撑界面（msi）提高了钌基催化剂的性能。通过系统表征，发现适当延长溶剂热时间可以提高tio2的结晶度，增加{0 0 1}晶面的暴露度。结果表明，Ru/HATNs催化剂上酸位和配位不饱和（cu）五重配位Ti （Ti5c）原子的数量增加。前者通过在酸位上加氢使苯的周转率（TOF）提高，后者提高了环己烯的选择性。在Ru/HATNs-24催化剂上，暴露{0 0 1}面最多的Ru/HATNs-24催化剂的初始选择性和产率分别达到83%和51%。环己烯的动力学分析和程序升温解吸（TPD）结果表明，{0 0 1}面上的cuti5原子比环己烯的加氢速率更快，降低了环己烯的吸附位置和吸附容量，减弱了环己烯的吸附强度，这是选择性增强的原因。
We devised ruthenium-based catalysts with hierarchical anatase TiO2nanospheres (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 TiO2crystallinity 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 (Ti5c) atoms on the Ru/HATNs 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 thecusTi5catoms on the {0 0 1} 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.