A new approach towards the synthesis of nitrogen-doped graphene/MnO2 hybrids for ultralong cycle-life lithium ion batteries

Abstract

A new approach using polypyrrole as the nitrogen source has been demonstrated for the fabrication of nitrogen-doped graphene, which subsequently served as nucleation centers for the growth of metal oxides. The thin layers of the nitrogen-doped graphene are not only used as conductive pathways accelerating the electrical conductivity of metal oxides but also serve as buffer layers to improve the electrical contact with metal oxide nanostructures during the delithiation/lithiation of lithium ions. As anodes for lithium ion batteries, the nitrogen-doped graphene and their hybrids with MnO₂ nanorods exhibit exceptionally excellent capacity retention for 3000 cycles at 2500 mA g⁻¹, and ultrafast rate capability, which pave the way for developing electrode materials for long cycle-life energy storage devices.