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Effect of aluminum vacancies on the H2O2 or H2O interaction with a gamma-AlOOH surface. A solid-state DFT study |
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| Authors: | Alexander G Medvedev Alexey A Mikhaylov Ivan Yu Chernyshov Mikhail V Vener Ovadia Lev Petr V Prikhodchenko |
| Institution: | 1. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russia;2. Department of Quantum Chemistry, Mendeleev University of Chemical Technology, Moscow, Russia;3. Casali Center of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel |
| Abstract: | The adsorption of a single H2O2 or H2O molecule on a family of periodic slab models of γ-AlOOH is studied by solid-state DFT. The single H2O2 or Н2О molecule interacts with the perfect (010) slab by intermolecular hydrogen bonds (H-bonds). In the models of γ-AlOOH with oxygen and aluminum vacancies, H2O2 or Н2О also forms covalent O∙∙∙Al bonds. The energies of covalent O∙∙∙Al and H-bonds are estimated by a combined approach based on simultaneous consideration of the total binding energies with BSSE correction and empirical schemes of the Н-bond energy evaluation. The O∙∙∙Al bond energy ranges from ~75 to ~156 kJ mol−1. The total energy of H-bond interactions in the case of H2O2 exceeds that of Н2О by ~30 kJ mol−1 for all considered slab models. In contrast to Н2О, a H2O2 molecule always forms two H-bonds as the proton donor. The energy of these bonds noticeably increase on defect γ-AlOOH surfaces in comparison with the perfect slab due to formation of short (strong) H-bonds by adsorbed H2O2. |
| Keywords: | catalytic center intermolecular H-bond energy/enthalpy oxygen and aluminum vacancies perfect and defect slab models the Bader analysis of periodic electron density |