Synthesis and high-rate performance of spinel Li4Ti5O12 with core–shell hierarchical macro–mesoporous structure

Abstract

The spinel Li₄Ti₅O₁₂ with a core–shell hierarchical macro–mesoporous structure has been synthesized via a hydrothermal reaction followed by a subsequent calcination step. Scanning electron microscopy and transmission electron microscopy show that the hydrothermal reaction time greatly influences the structure of the spinel Li₄Ti₅O₁₂ through the Ostwald ripening process. An N₂ adsorption–desorption study and mercury intrusion porosimetry measurements show that the optimized product has a high specific surface area of 77.14 m² g⁻¹ with meso- and macropores. Used as the anode material for lithium-ion batteries, the spinel Li₄Ti₅O₁₂ exhibits an excellent high-rate performance with a discharge specific capacity of 117.9 mA h g⁻¹ at a rate of 10 C (1700 mA g⁻¹).