Water facilitates oxygen migration on gold surfaces

Oxygen exchange between surface oxygen atom and isotopic labeled water vapor through transient hydroxyl pairs on Au(110) surface.

Density Functional Theory Study of H2O Molecules on Cr2O3 Surfaces

In order to understand the reactivity of Cr2O3 surface towards H2O molecule, the optimized structure, electronic structure, and the behavior of adsorbates were examined using a first-principles calculation based on density-functional theory (DFT). H2O coverages varying from a quarter to two monolayers (MLs) were considered. At a low coverage, the oxygen atom of H2O adsorbs on the Cr atom of the outermost Cr2O3 surface layer, the entire H2O molecule is slanted at the direction of a hollow site, and a molecular plane is nearly parallel to the surface. The hydrogen bond is formed between the surface oxygen atom and the hydrogen atom of H2O molecule. From the optimized structure, the H2O dissociation mechanism which passes through a transition state is guessed. For 0.5ML coverage the obtained absorption energy is-82.5 kJ/mol. Our results are in good agreement with other reported theoretical and experimental results.

Li Storage on TCNE and TCNE-(Doped)-Graphene Complexes: a Computational Study

ABSTRACTLi attachment to free tetracyanoethylene (TCNE) molecules and TCNE adsorbed on doped graphene is studied using density functional theory. While TCNE is adsorbed only weakly on ideal graphene, we identified a configuration in which TCNE is chemisorbed on Al-doped graphene via its C atom and a surface oxygen atom. Up to four Li atoms can be stored on both free and adsorbed TCNE with binding energies stronger than cohesive energy of the Li metal. TCNE immobilized on the conducting graphene-based substrate could therefore become an efficient anode material for organic Li ion batteries.