In-situ One-step Hydrothermal Synthesis of a Lead Germanate-Graphene Composite as a Novel Anode Material for Lithium-Ion Batteries

摘要

Lead germanate-graphene nanosheets (PbGeO₃-GNS) composites have been prepared by an efficient one-step, in-situ hydrothermal method and were used as anode materials for Li-ion batteries (LIBs). The PbGeO₃ nanowires, around 100–200?nm in diameter, are highly encapsulated in a graphene matrix. The lithiation and de-lithiation reaction mechanisms of the PbGeO₃ anode during the charge-discharge processes have been investigated by X-ray diffraction and electrochemical characterization. Compared with pure PbGeO₃ anode, dramatic improvements in the electrochemical performance of the composite anodes have been obtained. In the voltage window of 0.01–1.50?V, the composite anode with 20?wt.% GNS delivers a discharge capacity of 607?mAh g?1 at 100?mA g?1 after 50 cycles. Even at a high current density of 1600?mA g?1, a capacity of 406?mAh g?1 can be achieved. Therefore, the PbGeO₃-GNS composite can be considered as a potential anode material for lithium ion batteries.