Atomistic Simulation Studies of the Bulk Lithiated TiO$_2 $

TiO$_2$ has been confirmed as a safe anode material in lithium ion batteries due to its higher Li-insertion potential, (1.5V) in comparison with commercialised carbon anode materials. In the current study, amorphisation recrystallization method is used to produce bulk TiO$_2$ with a brookite structure and lithium is inserted at different concentrations. In accordance with pair distribution function experiments [1], it is found that lithiation tends to amorphise the structures. Simulated X-ray diffraction patterns are produced from such structures and compared with the experimental XRDs. Microstructures of TiO$_2$ are generated and are found to be highly twinned hence forming straight and zigzag tunnels. The microstructures of lithiated TiO$_2$ display limited twinning and tunnels with less pathways available for lithium transport. The microstructures are compared with those of nanostructural TiO$_2$ and suggestions for the preference of the latter in anodes are put forward. \\[4pt] [1] D. Dambournet, K. W. Chapman, M.V. Koudriachova, P.J. Chupas, I. Belharouak, and K. Amine, Inorg. Chem. 2011, 50, 5855--5857.