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W. Mayr-Schmölzer, F. Mittendorfer, J. Redinger:
"Adsorption of a superoxo O₂- species on the pure and Ca-doped Sr₃Ru₂O₇(001) surface";
Surface Science, 680 (2019), 24 - 31.

Only recently, the activation of oxygen molecules on clean defect-free transition metal oxide surfaces has been reported, for example on the CaO-terminated surface of the Ruddelsden-Popper perovskite Ca3Ru2O7(001). In this work we show that oxygen molecules adsorb as an activated superoxo species on a clean SrO-terminated surface of Sr3Ru2O7 (001). At all coverages, the electrons activating the molecule originate from the subsurface RuO2 layer. At low coverages, the presence of a Ca dopant in the terminating SrO layer slightly increases the adsorption energy. At high coverage, DFT predicts a flat potential energy surface and a preferred adsorption of the O2- near surface cations. Advanced many-electron calculations (RPA) predict adsorption energies of −0.99 eV and −0.49 eV per O2 molecule for low and high coverages, respectively, and a preference for forming line-like structures in the latter case.

Strontium ruthenate Sr3Ru2O7 Oxygen Superoxo O2 minus DFT GW RPA