A high-performance anode material based on FeMnO₃/graphene composite

Transition metal oxides are attractive as anode materials in lithium-ion batteries for their high theoretical capacity and good performance. In this work, an anode material based on manganese-based oxide FeMnO₃ in LIBs is investigated for the first time. FeMnO₃ is prepared with graphene and the FeMnO₃/graphene composite exhibits a high discharge capacity of 1155.3 mAh g⁻¹ after 300 cycles at 200 mA g⁻¹, as well as a superior rate performance of 851.7 mAh g⁻¹ at a current density of 3200 mA g⁻¹. The observed extraordinary performance is believed to be attributed to the combination of the intrinsically high capacity of FeMnO₃, a large surface area of 89.65 m² g⁻¹ and good electrical conductivity of the FeMnO₃/graphene composite. To help clarify the properties of this new material, we employ first principles calculations to determine the structural stability, electronic structure, and Li ion diffusivity of FeMnO₃. The calculations show that FeMnO₃ has a relatively low band gap (an indication of reasonable electrical conductivity) and Li ions exhibit a large room temperature diffusivity in FeMnO₃.