Thermodynamic functions and vibrational properties of Li intercalation in TiO2(B)

Abstract

In this work, Li doped TiO2(B) was modelled throughout the implementation of density functional theory with Hubbard methodology (DFT + U) in order to understand its vibrational and thermodynamics properties. Firstly, we performed structural, electronic structure and charge density difference studies in order to find accurately modelled systems. The electronic structure analysis shows that the lithiated systems have a metallic character and a n-type behavior, also the asymmetric DOS reveals that a small induced magnetic moment is present. The charge density difference analysis confirmed that the charge transfer is from the Li to the oxide. The vibrational properties studies present the undiscovered irreducible representation of the Li-TiO2(B) systems and its phononic densities. Moreover, the Raman spectroscopy studies of the bulk show great correspondence with experimental literature and the novel spectra obtained of the doped systems show a dispersion and displacement of the peaks. Additionally, the thermodynamic properties studies show evidence that both doped systems show promising features. Therefore, the results obtained here are innovative and can be used as reference connected with future experimental studies of this material, which has potential to be employed as a Li-ion battery anode.