Hydrogen bonding between a water molecule and electronegative additives (O or Cl-) on a Pt(111) surface

Water adsorption on Pt(111) surfaces treated with oxygen or hydrogen chloride at 20 K has been studied by Fourier transform infrared spectroscopy and scanning tunneling microscopy. Water molecules chemisorb predominantly on the sites of the electronegative additives (O or Cl-), forming hydrogen bonds of O-H⋯O or O-H⋯Cl-. On a Pt(111)-2×2-O surface, water adsorption produces species (O(D2O)), monomeric water (D2O), (O(D2O)2) and ring tetramer-like cluster (O(D2O)3) on a Pt(111) surface. On a Pt(111)-3×3-Cl- (θ=0.44) surface, water adsorption gives rise to a Pt(111)-(4×2)-(H3O++Cl-) co-adsorption structure to form a hydrogen-bonding network between Cl- and H3O+ ions.