Hydration of the β-MnO2 (110), (100), and (101) surfaces is investigated using a combination of periodic density functional theory and ab initio thermodynamics. Fully hydrated surfaces are found to be significantly more stable than the stoichiometric ones up to temperatures in the range of 650 K to 730 K at ambient oxygen and water partial pressures. A mixture of molecular and dissociative water adsorption is predicted to occur on the (110) and (101) surfaces, while the (100) surface does not dissociate water. Differences in surface relaxations and vibrational spectra are discussed and can be used to identify the type of adsorption mode.
Citation: Journal of Physical Chemistry C
Pub Type: Journals
ab initio thermodynamics, density functional theory, manganese dioxide, water adsorption, surfaces