标题：Atomic Pt and molecular H _2O adsorptions on SrTiO _3 with and without Nb-doping: Electron trapping center and mediating roles of Pt in charge transfer from semiconductor to water
作者：Wei, W.;Dai, Y.;Guo, M.;Ma, Y.;Huang, B.
作者机构：School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Shanda South Road 27, Jinan 250100, China;Sch
来源：Journal of Solid State Chemistry
关键词：Charge transfer;DFT calculation;H _2O adsorption;Pt adsorption;SrTiO _3 (0 0 1) surface
摘要：H _2O adsorption on SrO-terminated SrTiO _3 (0 0 1) surface has been investigated with the first-principles calculation based on DFT. An energy barrier of 0.221 eV for H _2O dissociation is obtained, which illustrates a spontaneous dissociation. H and O atoms on the SrO-termination of (0 0 1) surface recombine readily. It demonstrates that Pt induces surface dipole moment and changes the surface work function. Adsorption of atomic Pt on SrO-termination of Nb-doped SrTiO _3 (0 0 1) surface indicates charge transfer from the surface to Pt, i.e., Pt is negatively charged. Fukui functions illustrate the role Pt played in mediating charge transfer from (0 0 1) surface to targets adsorbed on Pt. H _2O adsorption on the Pt atom supported on Nb-doped SrTiO _3 confirms the charge transfer from semiconductor containing electrons to target species, which is mediated by metal. Charge transfer from negatively charged Pt to H _2O weakens (activates) the HO bonds in molecule H _2O.