Solid–liquid phase epitaxial growth of Li4Ti5O12 thin film

Abstract

A thin film of Li4Ti5O12, a candidate anode material for solid-state Li-ion batteries, was heteroepitaxially grown on a (001) SrTiO3 substrate using solid–liquid phase epitaxy. An amorphous Li4Ti5O12 film deposited at room temperature was first heated with LiNO3 powder in air and then washed with distilled water. The Li4Ti5O12 epitaxial film was obtained by heating with molten LiNO3 at 600 °C; the liquid LiNO3 completely covered the film, suppressing the formation of Li deficiencies and enhancing the low-temperature crystal growth. Solid–liquid phase epitaxy is a powerful approach to grow Li-containing-oxide films, which are difficult to fabricate because of the loss of Li species at high temperature.