Preparation of TiO2 nanosheets and Li4Ti5O12 anode material from natural ilmenite

We demonstrate a simple, improved and novel approach for the synthesis of a kind of anatase TiO2 nanosheets and Li4Ti5O12 anode material with excellent electrochemical performance from the natural ilmenite. We use the H2O2 to leach the Ti from the hydrolyzed titania residue under alkaline condition of leaching. Before boiling, the LiOH was added into the leach solution. The obtained precipitation of titanium dioxide hydrate can be purified and refined into special nanostructure by the addition of LiOH. SEM and XRD show that the as-prepared TiO2 are special nanostructure and well-crystallized anatase phase. The analysis of elemental contents reveals that the content percent of TiO2 in as-prepared TiO2 nanosheets is more than 99%. Moreover, the titanium dioxide hydrate can be used to prepare Li4Ti5O12 anode material directly. The obtained Li4Ti5O12 shows charge specific capacities of 161,138 and 113 mA hg− 1 at 0.1C, 0.5C and 1C rates, respectively, and excellent cycling stability.

Graphical abstractThe TiO2 nanosheets and Li4Ti5O12 anode material are prepared from ilmenite. SEM image (Fig. a) shows that the as-prepared TiO2 is petal-shaped nanosheet. From the charge and discharge curves (Fig. b), the as-prepared Li4Ti5O12 shows a capacity of 161, 138 and 112 mA hg− 1 at 0.1C, 0.5C and 1C rate, respectively.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► We propose a novel approach for the synthesis of TiO2 and Li4Ti5O12 from ilmenite. ► The anatase TiO2 nanosheets have a special nanostructure and show great value. ► The as-prepared Li4Ti5O12 shows excellent electrochemical performance.