A novel Fe3O4/buckypaper composite as free-standing anode for lithium-ion battery

•We have successfully electrochemically deposited Fe3O4 particles on buckypaper.•The metallic current collector-free Fe3O4/buckypaper anode can significantly reduce the mass of the anode.•The flexible anode achieves a higher initial reversible capacity and more stable performance.•This work provides a new way to develop novel anodic structure for high capacity and less weight lithium-ion battery.

The octahedral Fe3O4 (magnetite) nanoparticles were electrochemically grown on self-supported buckypaper and characterized by XRD, SEM, Raman and TGA. It could be used as a kind of metallic current collector-free anode for lithium ion battery, which would significantly reduce the mass of the whole anode by 66%. The new flexible Fe3O4/buckypaper composite anode achieves a higher initial reversible capacity of 1120 mAh g−1 and exhibits more stable performance compared with Fe3O4 anode coated on Cu foil by traditional electrode-fabrication technique. This is due to that the flexible 3D porous-structured Fe3O4/buckypaper composite is light weight and can accommodate the volume change of Fe3O4 during the lithiation/delithiation process, and promotes the diffusion and transfer of lithium ion and electron, respectively. Moreover, this buckypaper/Fe3O4 composite anode displays excellent rate capability, which maintains a discharge specific capacity of 210 mAh g−1 when the applied current rate is 10 °C and still delivers 1150 mAh g−1 after returning to 0.2 °C. Our work provides a new way to develop novel electrode structure for light-weighted and flexible lithium-ion battery.