Magnetic tubular carbon nanofibers as anode electrodes for high-performance lithium-ion batteries

Novel magnetic tubular carbon nanofibers (MTCFs) are prepared through the combination technique of hypercrosslinking, control extraction, and carbonization. The diameter of MTCFs is mainly concentrated between 90 and 120 nm, and the average tube diameter is about 30 nm. A trace amount of Fe₃O₄ exists inside the MTCFs with a particle size of 3 nm, which is formed by in situ conversion of the catalyst (FeCl₃) for the hypercrosslinking reaction. The MTCFs with high surface area (448.74 m² g⁻¹) and porous wall are used as anode material for lithium-ion batteries. The electrochemical properties of MTCFs are compared, and tubular carbon nanofibers (TCFs) prepared by the complete extraction. Electrochemical analysis shows that the introduction of Fe₃O₄ nanoparticles makes MTCFs have higher reversible capacity and better rate performance. MTCFs exhibit high reversible specific capacity of 1011.7 mAh g⁻¹ after 150 cycles at current density of 100 mA g⁻¹. Even at high current density of 3000 mA g⁻¹, a remarkable reversible capacity of 270.0 mAh g⁻¹ is still delivered. Thus, the novel MTCFs show potential application value in anode material for high-performance lithium-ion battery.