Preparation And Electrochemical Performances Of Spinel Li₄Ti₅O₁₂/RGO

Spinel lithium titanate (Li4Ti5O12) has been intensively investigated as a promising anode candidate for high-power lithium-ion batteries (LIBs) due to its rapid Li+ diffusivity, remarkable structural stability and excellent safety. Although spinel Li4Ti5O12 has been considered as a promising alternative material to carbonaceous materials because of its excellent lithium-ion insertion/extraction reversibility and a higher Li-insertion potential (1.55 V), inherently low electronic conductivity seriously depresses its high rate capability for LIBs. Intense research works have been performed to improve its power performances.Developing nanostructured spinel Li4Ti5O12 with extra surface lithium storage is a novel and attractive strategy to enhance the reversible capacity and high rate performance. In this paper, nanoparticles-constructed Li4Ti5O12 nanosheets with extra surface lithium storage capability are successfully prepared for the first time. The newly prepared nanoparticles-constructed Li4Ti5O12 nanosheets display enhanced electrochemical performances, demonstrating ultrahigh reversible capacity of 173 mAh g-1 at 0.5 C and superior rate performance of more than 145.5 mAh g-1 at 30 C between 1.0 and 2.5 V vs. Li+/Li. The beneficial surface lithium storage is mainly attributed to their better crystallinity and higher specific surface area.Graphene has excellent electrical conductivity, high strength and large specific surface area. Spinel Li4Ti5O12 (LTO) and reduced graphene oxide (rGO) are attractive anode materials for lithium ion batteries (LIBs). We synthesized nanoparticles Li4Ti5O12/RGO composite by one step hydrothermal method. We used glucose as a novel linker reagent and reduced agent. The morphologies of the sample was investigated by TEM and SEM images. It was worth noting that composite displayed ultrahigh reversible capacity of 203 mAhg-1 at 0.5 C and superior rate performance of more than 168 mAhg-1 at 30 C between 1.0 and 2.5 V vs. Li+/Li.We reported a facile one-step hydrothermal method in preparation of a nanocomposite anode consisting of well-dispersed mesoporous Li4Ti5O12 particles onto rGO. An important reaction step involved glucose as a novel linker agent and reducing agent during synthesis. It was found to prevent the aggregation of Li4Ti5O12 particles, and result in mesoporous structures in nanocomposites. In particular, the nanocomposite anode delivered an ultrahigh reversible capacity of 193 mAhg-1 at 0.5C and superior rate performance capable of retaining a capacity of 168 mAhg-1 at 30 C between 1.0 and 2.5 V. Therefore, the newly prepared mesoporous Li4Ti5O12/rGO nanocomposite with increased surface lithium storage capability would provide a new opportunity to develop high-power anode materials for LIBs.