Insight into the adsorption and dissociation of CH_4 on Pt(h k l) surfaces: A theoretical study

摘要

A density functional theory slab calculations of CH_4 dissociation on Pt(h k l) surfaces have been systematically presented. On the basis of the energetic analysis, the favorable adsorption sites and stable configurations of CH_x(x=0-4) and H species on Pt(111),Pt(1 1 0) and Pt(l 00) surfaces are first obtained, respectively. Afterwards, the most stable configurations of coadsorbed CH_x/H(x=0-3) are located. Further, the kinetic and thermodynamical results of CH_4 dissociation on Pt(h k l) surface suggest that CH is the most abundant CH_x species. Our results mean that Pt catalyst can resist the carbon deposition in the CH4 dissociation, which can give a microscopic reason that why Pt catalyst can lead to lower carbon deposition and show a high activity in the reaction related to CH_4.