Defects, Diffusion, and Dopants in LiTiO: Atomistic Simulation Study.

In this study, force field-based simulations are employed to examine the defects in Li-ion diffusion pathways together with activation energies and a solution of dopants in LiTiO. The lowest defect energy process is found to be the Li Frenkel (0.66 eV/defect), inferring that this defect process is most likely to occur. This study further identifies that cation exchange (Li-Ti) disorder is the second lowest defect energy process. Long-range diffusion of Li-ion is observed in the -plane with activation energy of 0.25 eV, inferring that Li ions move fast in this material. The most promising trivalent dopant at the Ti site is Co, which would create more Li interstitials in the lattice required for high capacity. The favorable isovalent dopant is the Ge at the Ti site, which may alter the mechanical property of this material. The electronic structures of the favorable dopants are analyzed using density functional theory (DFT) calculations.