Electrochemical properties of nano-sized Fe₂O₃-loaded carbon as a lithium battery anode

Nano-sized Fe₂O₃-loaded carbon material was prepared by loading Fe₂O₃ on carbon using a chemical method. Fe(NO₃)₃ was impregnated on carbon in an aqueous solution, and the mixture was dried and then calcined for 1 h at 400 °C in flowing Ar. Transmission electron microscopy (TEM) coupled with X-ray diffraction measurements revealed that small Fe₂O₃ particles (a few tenths of nanometers) were distributed on the carbon surface. The obtained nano-sized Fe₂O₃-loaded carbon material acted as an anode in a Li cell. High charge capacities of over 1000 mAh g^-1 (reduction of Fe₂O₃) in the first charge process suggested that Fe³⁺ in Fe₂O₃ was electrochemically reduced to Fe⁰. Investigation of the charge material by X-ray photoelectron spectroscopy (XPS) confirmed that Fe³⁺ is reduced to Fe⁰. Nano-sized Fe₂O₃-loaded acetylene black (AB), which, due to the larger surface area of AB, gave a greater distribution of nano-sized Fe₂O₃ particles than graphite, provided a larger capacity than nano-sized Fe₂O₃-loaded graphite.