Fe2O3-MWNTs Composite with Reinforced Concrete Structure as High-performance Anode Material for Lithium-ion Batteries

AFe₂O₃-MWNTs(multi-walled carbon nanotubes) composite with a reinforced concrete structure was fabricated employing a two-step method, which involves a sol-gel process followed by high-temperature in situ sintering. This Fe₂O₃-MWNTs composite, intended to be used as an anode material for lithium-ion batteries, maintained a reversible capacity as high as 896.3 mA·h/g after 100 cycles at a current density of 100 mA/g and the initial coulombic efficiency reached 75.5%. The rate capabilities of the Fe₂O₃-MWNTs composite, evaluated using the ratios of capacity at 100, 200, 500, 1000, 2000 and 100 mA/g after every 10 cycles, were determined to be 904.7, 852.1, 759.0, 653.8, 566.8 and 866.3 mA·h/g, respectively. Such a superior electrochemical performance of the Fe₂O₃-MWNTs composite is mainly attributed to the reinforced concrete construction, in which the MWNTs function as the skeleton and conductive network. Such a structure contributes to shortening the transport pathways for both Li⁺ and electrons, enhancing conductivity and accommodating volume expansion during prolonged cycling. This Fe₂O₃-MWNTs composite with the designed structure is a promising anode material for high-performance lithium-ion batteries.