Porous nitrogen-doped graphene nanofibers comprising metal organic framework-derived hollow and ultrafine layered double metal oxide nanocrystals as high-performance anodes for lithium-ion batteries

Abstract

The growth of unique nanostructures with multicomponent systems is a renowned strategy for developing advanced materials for various energy storage applications. Herein, we utilize a facile approach to synthesize multicomponent high-performance nanofibers as anodes that comprises hierarchically porous and self-supporting N-doped reduced graphene oxide (N-doped rGO) matrix grafted with metal-organic framework (MOF)-derived hollow and ultrafine layered double metal (Ni and Co) oxide (LDO) nanocrystals [P-(Ni, Co)O/rGO NFs]. The porous and highly conductive N-doped rGO scaffold not only provides structural integrity but also offers short Li-ion diffusion pathways along with enormous conductive channels for rapid charge transfer during cycling. The hollow and ultrafine LDO nanocrystals also provide sufficient space for rapid reaction sites and to absorb the severe volume stress generated during repeated charge-discharge cycles owing to their rich oxidation states. The Li-cell utilizing the P-(Ni, Co)O/rGO NFs as anodes exhibits overall enhanced electrochemical performance with prolonged cycling stability (907 mA h g−1 at the end of 500th cycle) and a satisfactory high-rate capability (519 mA h g−1 at 5.0 A g−1).