Influence of vanadium, cobalt-codoping on electrochemical performance of titanium dioxide bronze nanobelts used as lithium ion battery anodes

In this work, V, Co-codoped TiO₂(B) samples are synthesized through a hydrothermal method, and used as negative electrode materials for lithium ion batteries. The amount of dopants is varied in order to investigate their influence on electrochemical properties. The formation of V, Co-codoped TiO₂(B) nanobelts with widths of 20 and 60 nm is demonstrated using X-ray diffraction, X-ray photoelectron spectroscopy, inductively coupled plasma–optical emission spectrometry and field-emission scanning electron microscopy analyses. In addition, the electrochemical properties of the samples are tested by cyclic voltammetry, charging/discharging, and cyclic performance techniques. Compared to other samples, TiO₂(B) nanobelts codoped with 2.5 wt% Co–2.5 wt% V, shows the best cycling performance, and exhibits the first high capacity of 264.86 mAh g⁻¹ [x = 0.79, Li_XTiO₂(B)] at a rate of 0.5 C due to the improved Li⁺ diffusion and electronic conductivity, induced by crystal defects and oxygen vacancy. This electrode demonstrates excellent cyclability and has more than 96% capacity even after 50 cycles. It is concluded that the concentration of dopants in the TiO₂(B) structure plays an effective role in improving the electrochemical performance of electrodes.