文摘
H2O adsorption on SrO-terminated SrTiO3 (0 0 1) surface has been investigated with the first-principles calculation based on DFT. An energy barrier of 0.221 eV for H2O 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 SrTiO3 (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. H2O adsorption on the Pt atom supported on Nb-doped SrTiO3 confirms the charge transfer from semiconductor containing electrons to target species, which is mediated by metal. Charge transfer from negatively charged Pt to H2O weakens (activates) the H-O bonds in molecule H2O.