Electrochemical performance of hollow α-Fe₂O₃ spheres as anode material for lithium-ion battery

Hollow α-Fe₂O₃ spheres were synthesized by a facile hydrothermal method followed by a calcination step. The crystalline structure and morphology of the synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The morphology of the sample consisted of porous hollow spheres that ranged about hundreds of nanometers and were composed of well crystallized nanoparticles about a dozen nm. The electrochemical properties of the sample were evaluated by cyclic voltammetry (CV) and charge/discharge measurements. The discharge/charge capacities in the first cycle achieved 1336/934 mAh g^-1 at the rate of 0. 2 C. The reversible capacity in the 50th cycle remained 840 mAh g^-1 with impressive retention rate of 90%. This good lithium storage property was probably ascribed to the porous and hollow structure and nanoscale a-Fe₂O₃ particles, which enlarged the surface area and shortened the pathway for lithium ion migration. The appealing electrochemical capability indicated the potential implementation of hollow Fe2O3 spheres as anode material for future lithium-ion battery.