Modelling and synthesis of Magnéli Phases in ordered titanium oxide nanotubes with preserved morphology

). Experimental results from scanning electron microscopy (SEM), X-ray diffraction (XRD), scanning transmission electron microscopy (S/TEM), and Raman spectroscopy were combined with first principle calculations to develop an understanding of the sequential phase transformations during annealing. A predictive model was developed using density functional theory (DFT) to potentially predict the titanium oxides formed and their stability with reference to the mole fraction of oxygen. The change in the density of states (DOS), band structure, optical properties, and stability of phases are also discussed using DFT simulations. The combination of experimental characterization and modelling helped to understand the nucleation of anatase and rutile and the reorganization of these phases to form Magnéli phases on the anodized amorphous NTs through annealing treatment.