Three-dimensionally macroporous graphene-supported Fe3O4 composite as anode material for Li-ion batteries with long cycling life and ultrahigh rate capability

Fe 3 O 4 is an attractive conversion reaction-based anode material with high theoretical capacity (928 mA h g −1 ). However, the poor cycling and rate performance hinder its applications in Li-ion batteries. In this work, we report an effective strategy to synthesize three-dimensionally macroporous graphene-supported Fe 3 O 4 hybrid composite. Benefiting from advantage of the special structure, the hybrid composite exhibits excellent Li + storage performance, delivering a high reversible capacity of 980 mA h g −1 at the current density of 4 A g −1 even after 470 cycles and ultrahigh rate capability (293 mA h g −1 even at current density of 20 A g −1 ).