Anchoring Nanostructured Manganese Fluoride on Few-Layer Graphene Nanosheets as Anode for Enhanced Lithium Storage

Manganese fluoride (MnF₂)/few-layer graphene nanosheets (GNS) composites are successfully prepared via a facile solvothermal method. It is found that in situ formed tetragonal MnF₂ submicron crystals (50-200 nm) with good crystallinity anchoring homogeneously onto conducting GNS, allows the electrically insulating MnF₂ particles to be wired up to the current collector with enhanced electron transport pathway. The MnF₂/GNS composites act as anode in LIBs and display prominently improved electrochemical performance in comparison to that of pure MnF₂, on account of the close interactions between the underlying graphene nanosheets and MnF₂ particles grown atop. Distinctly enhanced capacity as high as 489 mAh g^-1 after 100 cycles can be obtained at 600 mA g^-1, while the self-activation process can be greatly accelerated at 6000 mA g^-1 with a maximum specific capacity of 530 mAh g^-1. With long cycling stability for 4000 cycles at 6000 mA g^-1, the MnF₂/GNS composite can be deemed as an attractive candidate anode for high-capacity, long cycle life, and environmentally friendly LIBs.