  We analyze, with Density Functional Theory (DFT) calculations, the adsorption
energies of Li$_2$O$_2$, Na$_2$O$_2$ and NaO$_2$ on clean and oxygen passivated
TiC (111) surfaces. We show, that after deposition of two molecular layers of
alkali metal oxides, the initial state of the TiC surface becomes unimportant
for the adsorption energy and that all adsorption energies approach their
native crystal values. The structure of the adsorbed molecular layers is
analyzed and compared to their native oxide crystal structure. Finally, we
discuss the possible implications for electrode optimization for Li-air and
Na-air batteries.
