Electrochemical Lithium and sodium insertion from aqueous solutions into TiO2 films deposited on stainless steel

Nanostructured titanium oxide thin films were fabricated directly by an anodic electrodeposition using an aqueous TiCl₃ solution. Structure and morphology of thin layers of TiO₂ deposited on stainless steel and annealed at different temperatures were characterized by X-ray diffraction (XRD) and microscopy techniques (SEM, AFM). Two phases of titanium oxide observed at annealing temperature 350 °C (rutile and anatase) converts after annealing at 450 °C into anatase well-crystallized phase. The grain size was of about 20-30 nm. By AFM analysis, roughness around 50 nm was observed. Cyclic voltammograms (CVs) showed that annealed titanium oxide films have exhibited reversible insertion/de-insertion of lithium ion and of sodium in LiOH or NaOH aqueous electrolyte.