Reduced graphene oxide wrapped ZnMn2O4/carbon nanofibers for long-life lithium-ion batteries

ZnMn2O4 is regarded as one of the potential anode materials for lithium-ion batteries (LIBs), due to its high theoretical specific capacity (784 mAh g−1). Unfortunately, the bulk ZnMn2O4 presents an inferior electrochemical performance resulting from the large volume change during the charge-discharge process. In this paper, we report the synthesis and electrochemical properties of ZnMn2O4 nanoparticles (NPs) that are homogeneously distributed in connective network porous carbon nanofibers wrapped by reduced graphene oxide sheets. The distinctive structure of this composite not only provides enough voids to storage Li-ions and buffer the volume expansion of the ZnMn2O4 NPs, but also offers a continuous conducting network for Li-ion and electron transportation, resulting in significantly improved electrochemical performances. As binder-free electrodes for LIBs, an optimized ZnMn2O4@rGO-CNFs sample exhibits a reversible capacity of 1142 mAh g−1 at 100 mA g−1 over 100 cycles, and a stable capacity of 659 mAh g−1 after 1000 cycles at a large current density of 2000 mA g−1, enabling ZnMn2O4 a promising electrode candidate for LIBs.