MOFs-derived metal oxides inlayed in carbon nanofibers as anode materials for high-performance lithium-ion batteries

Abstract

The lithium storage performance of metal oxides often suffer rapid capacity fading and poor rate performance due to their huge volume expansion during repeated charge and discharge processes. Herein, a facile strategy was adopted for constructing a three-dimensional (3D) interconnected conductive network. Metal-organic frameworks (MOFs)-derived metal oxides (Fe2O3, ZnO) were inlayed in carbon nanofibers through electrospinning and subsequent carbonization processes. As lithium-ion storage materials, the MOFs-derived metal oxide composite nanofibers exhibited a high specific capacity and an excellent rate capability due to the unique structural characteristics of high electrical conductivity, additional Li-storage sites, and defined frameworks. The Fe2O3@polyacrylonitrile (PAN) and ZnO@PAN composite nanofibers deliver high initial specific capacities of 1571.4 and 1053.8 mAh g−1 at 50 mA g−1, respectively. Moreover, Fe2O3@ PAN and ZnO@PAN composite nanofibers retained reversible specific capacities of 506.6 and 455.4 mAh g−1 at 1000 mA g−1 after 500 cycles, respectively. Additionally, the diffusion kinetics analysis indicated a relatively fast Li-ion diffusivity for the composite nanofibers.