文献类型：期刊文献

英文题名：Improved selectivity and coke resistance of core-shell alloy catalysts for propane dehydrogenation from first principles and microkinetic analysis

作者：Xiao, Ling[1]; Ma, Fang[1]; Zhu, Yi-An[1]; Sui, Zhi-Jun[1]; Zhou, Jing-Hong[1]; Zhou, Xing-Gui[1]; Chen, De[2]; Yuan, Wei-Kang[1]

机构：[1] UNILAB, State Key Laboratory of Chemical Engineering, Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China; [2] Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim, N-7491, Norway

年份：2019

卷号：377

外文期刊名：Chemical Engineering Journal

收录：EI(收录号：20184205949017)

语种：英文

外文关键词：Activation energy - Density functional theory - Metal nanoparticles - Catalyst selectivity - Charge transfer - Shells (structures) - Calculations - Transition metals - Propylene - Dehydrogenation - Electronic structure - Platinum alloys - Propane

摘要：Microkinetic analysis combined with the results obtained from density functional theory calculations has been performed to examine the catalytic activity and selectivity of Pt-based core-shell alloy catalysts for propane dehydrogenation. Calculated results indicate that substitution of 11 late transition metals for the core region of Pt nanoparticles would significantly modify the electronic structure of the surface Pt atoms through the strain effect and charge transfer. The core-shell catalysts are found to have less negative propylene adsorption energies and higher activation energies for the dehydrogenation reactions than Pt, thus giving rise to a lower catalytic activity and a higher selectivity toward propylene. Linear chemisorption energy and transition state energy scaling relations hold very well in the present work, and the adsorption energy of propylene is identified to be a good descriptor to represent the overall kinetics. The scaling relations also suggest that a higher catalyst selectivity toward propylene can only be achieved at the expense of a lower catalytic activity for propane dehydrogenation. If a compromise is made between catalytic activity and catalyst selectivity, Co@Pt is proposed to be the best core-shell catalyst for propane dehydrogenation. ? 2018 Elsevier B.V.