The facile preparation of hollow Fe₃O₄/C/CNT microspheres assisted by the spray drying method as an anode material for lithium-ion batteries

We have designed a facile process to synthesize the hollow Fe₃O₄/C/CNT microspheres through a spray drying method. The composite has both the high theoretical capacity of Fe₃O₄ and the great electronic conductivity of carbon nanotubes (CNTs). And the hollow structure built by spray drying is beneficial to relieve the volume change during conversion reaction. With the combination of Fe₃O₄ and carbon materials, the Fe₃O₄/C/CNT microspheres show a great electrochemical performance. It has maintained a high reversible capacity of 1200 mA h g⁻¹ after 100 cycles at the current density of 200 mA g⁻¹ and a specific capacity of 750 mA h g⁻¹ after 300 cycles at the current density of 1 A g⁻¹. The composite also shows a high initial coulombic efficiency of 75.7% at 200 mA g⁻¹. Hence, the high-performance hollow Fe₃O₄/C/CNTs microsphere is a promising substitute for anode material of lithium-ion batteries (LIBs). Furthermore, the spray draying method is widely used in industrial manufacture. Therefore, this composite has greater potential for a practical application.