Rapid synthesis of Li₄Ti₅O₁₂/graphene composite with superior rate capability by a microwave-assisted hydrothermal method

Li₄Ti₅O₁₂ microspheres composed of nanoflakes wrapped in graphene nanosheets have been synthesized by an advanced microwave-hydrothermal (MW-HT) method for the preparation following by an annealing step. Microwave-assisted synthesis processes are appealing, as they can rapidly synthesize materials with a high degree of control of particle size and morphology at low cost. The resultant composite reveals a unique loose structure which could avoid the restacking of graphene sheets and offer rapid lithium ion diffusion paths. Therefore the Li₄Ti₅O₁₂/graphene electrode has highly desirable properties: a specific capacity approaching the theoretical value, stable cycling, and exceptional rate capability. The composite also can be a good indicator of the remained charge and discharge capacity since it presents a curved charge and discharge line instead of a stable plateau.