Enhancing the kinetic lithium insertion in Li4Ti5O12 by introducing anatase TiO2

Li4Ti5O12 (LTO) is widely known as a stable and safe anode material for lithium -ion batteries (LIBs) owing to its so-called "zero-strain" effect. However, its low intrinsic conductivity and theoretical capacity limit its intensive application. In this work, we fabricated Li4Ti5O12/anatase TiO2 (LTO/AT) heterostructured nanosheets by a multi-step process, where the anatase phase could be facilely introduced into the main LTO phase by adjusting the amount of Li salt in the system. The presence of the AT phase could significantly enhance the kinetic insertion/extraction of Li+ in LTO, giving rise to much higher reversible capacities of LTO/AT at different C -rates than pure LTO and AT. Density functional theory (DFT) calculation results suggested that the interface between LTO and AT could reduce the diffusion barrier of Li atoms and enhance the electronic conductivity, accelerating the electrochemical kinetic process, and thus improving battery performance.