In this work we utilize experimental and simulation techniques to examine the molecular level interaction of water with a MnO(1 × 1) thin film deposited onto Ag(100). The formation of MnO(1 × 1)/Ag(100) was characterized by low energy electron diffraction and scanning tunneling microscopy. Density functional theory (DFT) shows MnO(1 × 1) is thermodynamically more stable than MnO(2 × 1) by ∼0.4 eV per MnO. Upon exposure to 2.5 Torr water vapor at room temperature, X-ray photoemission spectroscopy results show extensive surface hydroxylation attributed to reactivity at MnO(1 × 1) terrace sites. DFT calculations of a water monomer on MnO(1 × 1)/Ag(100) show the dissociated form is energetically more favorable than molecular adsorption, with a hydroxylation activation barrier 0.4 eV per H2O. These results are discussed and contrasted with previous studies of MgO/Ag(100) which show a stark difference in behavior for water dissociation.
Arble, C., Tong, X., Giordano, L., Ferrari, A., Newberg, J. (2016). Water dissociation on MnO(1 × 1)/Ag(100). PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 18(36), 25355-25363 [10.1039/c6cp04115a].
Water dissociation on MnO(1 × 1)/Ag(100)
Giordano L.;
2016
Abstract
In this work we utilize experimental and simulation techniques to examine the molecular level interaction of water with a MnO(1 × 1) thin film deposited onto Ag(100). The formation of MnO(1 × 1)/Ag(100) was characterized by low energy electron diffraction and scanning tunneling microscopy. Density functional theory (DFT) shows MnO(1 × 1) is thermodynamically more stable than MnO(2 × 1) by ∼0.4 eV per MnO. Upon exposure to 2.5 Torr water vapor at room temperature, X-ray photoemission spectroscopy results show extensive surface hydroxylation attributed to reactivity at MnO(1 × 1) terrace sites. DFT calculations of a water monomer on MnO(1 × 1)/Ag(100) show the dissociated form is energetically more favorable than molecular adsorption, with a hydroxylation activation barrier 0.4 eV per H2O. These results are discussed and contrasted with previous studies of MgO/Ag(100) which show a stark difference in behavior for water dissociation.
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