Adsorption and Deposition of Li2O2 on TiC{111} Surface

A recent experimental study from Bruce's group demonstrated the feasibility of TiC as a cathode material for Li air battery. We investigate Li2O2 adsorption and deposition on TiC{111} surface by periodic density functional theory calculation. The results showed that, upon interaction with Ti-terminated TiC{111} surface, Li2O2 clusters reassembled into a saturated periodic two atomic layer coating in which each O atom was bonded to three Ti atoms to form a O layer equivalent to the layer formed by O-2 surface oxidation, and the Li atoms sat on the top. The atomic arrangement of O and Li layers is the same as that of O(2)Li1 layers normal to <0001> direction in Li2O2 crystal structure. Interface models constructed based on this lead showed that the growth of Li2O2 can be continued through a surface conduction mechanism to form Li2O2 coating with lattice parameters almost identical to those of the standard Li2O2 unit cell. The results support the experimental discovery from Bruce's group. [GRAPHICS]