Nanostructured TiO2 as anode material for magnesium-ion batteries

The nanotubular structure of titanium dioxide (TiO 2 ) is most suitable for creating high-performance energy storage and conversion devices. This paper reports on the synthesis of an array of nanotubes (NTs) from TiO 2 by electrochemical anodization of titanium sheets using electrolytes based on fluorine and glycerol. The results of SEM and X-ray spectral analysis of the obtained material revealed the anatase phase of TiO 2 nanotubes with an inner diameter of 96–150 nm and a length of 0.6 ± 0.1 μm. The electrochemical behavior of the resulting electrode was studied in a solution of Mg(TFSI) 2 based on ethylene carbonate/dimethyl carbonate (1/1). From the cyclic voltammograms, the diffusion coefficient and rate constant were determined to be 1.51·10 −10 cm 2 ·s −1 , k = 1.55·10 −10 cm·s −1 (reduction), respectively. The value of the Coulomb efficiency at low discharge current is higher (88%) than at high discharge current (56%). At a high discharge current (1C), it is noticeable that the charge capacity in the cathodic process is much higher than in the anodic process.