Preparation and lithium intercalation behavior of TiO2 in aqueous solutions

The low crystalline or amorphous TiO2 was prepared by TiCl4 hydrolysis in aqueous solutions under different pH conditions at 45 °C. The products obtained at lower pH (1.23–3.10) appear to be nano-sized particles with poor crystalline anatase structure and an uniform particle size distribution, while the product prepared at pH 4.10 presents in a poor crystalline anatase structure and the regular morphology starts to disappear, and the products obtained at higher pH (>6.00) are amorphous and irregular morphology. The hydrolysis products obtained at pH 2.60 and 8.80 were heat-treated at 300, 400, 600, 700 and 800 °C for 3 h, respectively, to figure out the phase transition. The differences in phase transition process were observed, which verified the properties difference. The lithium intercalation abilities of the obtained TiO2 were studied. The results indicated that the TiO2 obtained at lower pH are more favorable for lithium intercalation and are better precursors.