Investigation of the Electrochemical Properties of the Anode of Na-Ion Battery Based on Nanotubular Anodic TiO2

Abstract

It is common practice to use mesoporous layers, nanofibers, and nanospheres of titanium oxide of various chemical and phase compositions as electrodes for microbatteries. Studies of the properties of TiO₂ nanotubes (TiO₂ NT’s) have shown the relevance of using it as an anode electrode for sodium-ion batteries. In this paper a method for modifying TiO₂ NT’s with the removal of the inner layer of nanotubes by etching in a mixture of sulfuric acid and hydrogen peroxide is proposed. It is demonstrated that the inner mesoporous layer of nanotubes hinders the embedding and extraction, respectively, of sodium ions into and from the structure of TiO₂ NT’s. Cyclic voltammetry studies show that after the removal of the inner part of the nanotubes, anodic and cathodic peaks appear, which are responsible for the extraction and intercalation of sodium ions, respectively. It is established that sodium ions are not intercalated into the crystal lattice of the TiO₂ NT’s sample after the etching of the inner layer, which indicates the reversibility of the ion introduction process. The studies have shown that TiO₂ NT’s can be used as an anode electrode in ionic accumulators and microbatteries due to the electrochemical characteristics and the possibility of various modifications of the TiO₂ NT’s array.