title: Hydrogen diffusion into the subsurfaces of model metal catalysts from first principles.
abstract: Diffusion pathways of atomic hydrogen on model catalyst surfaces and into subsurfaces are of great significance in the exploration of novel catalytic hydrogenation in heterogeneous catalysis. We present in detail the diffusion pathways of hydrogen on seven different open and closed model catalyst surfaces from first principles calculations. Seven transition metal catalysts with thirteen different crystal surfaces, i.e., Co(001), Ni(100) and Ni(111), Pd(100) and (111), Pt(100) and (111), Cu(100) and (111), Ag(100) and (111) and Au(100) and (111), are taken into account. Thirteen corresponding potential energy surfaces (PESs) are constructed for modelling hydrogen diffusion on these model catalyst surfaces and into the subsurfaces by interpolating ab initio density functional theory energy points (∼2000 for each surface). The minimum energy diffusion pathways for hydrogen on the surfaces and into the subsurfaces are globally searched for based on PESs using a mesh method, and are in excellent agreement with those calculated from the nudged elastic band method. Furthermore, the important substrate relaxation effect can decrease the diffusion barriers for hydrogen into catalyst subsurfaces. The high reactivity of subsurface reactants mainly comes from the residual energy of subsurface hydrogen emerging from the subsurface onto the surface.
authors.affiliation: Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001, China and State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China.
authors.forename: Xiangjian
authors.initials: X
authors.lastname: Shen
authors.affiliation: Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001, China.
authors.forename: Yuanjie
authors.initials: Y
authors.lastname: Li
authors.affiliation: Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001, China.
authors.forename: Xianglin
authors.initials: X
authors.lastname: Liu
authors.affiliation: Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Gao
authors.affiliation: Research Center of Heterogeneous Catalysis and Engineering Sciences, School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001, China and School of Mechanics and Engineering Science, Zhengzhou University, Zhengzhou 450001, China. liangtsh@zzu.edu.cn.
authors.forename: Tianshui
authors.identifier: http://orcid.org/0000-0001-5299-1836
authors.initials: T
authors.lastname: Liang