Nitrogen-Doped Graphene Nanosheet Coated Nanospherical Fe3O4 from Zeolitic Imidazolate Frameworks Template as Anode of Lithium Ion Batteries

Herein, a facile in situ self-assembly strategy is developed to fabricate two-dimensional nanospherical Fe3O4@nitrogen-doped graphene nanosheet (Fe3O4@NGNS) composite using Fe-based zeolitic imidazolate frameworks (Fe-ZIFs) and graphene oxide (GO) as the precursors. This in situ synthesis tactic can availably suppress both the agglomeration and the huge volume change of nanospherical Fe3O4. As an anode of lithium ion batteries, Fe3O4@NGNS exhibits preeminent cycle stability and rate performance, which inhabits a stable specific capacity of 502.3 mAh g–1 at the current density of 2 A g–1 after 200 cycles. Moreover, the electrode material easily recovered a large capacity of 1045.82 mAh g–1, after the current density returned to 0.1 A g–1, showing excellent reversibility. The enhanced electrochemical performance is attributed to the 2D architecture formed by the nanospherical Fe3O4 and graphene nanosheet, which offer additional space for the storage of electrolytes, thereby shorting the path of ion insertion/deinsertion. This renders Fe3O4@NGNS a promising high-performance anode candidate for lithium ion batteries.