Enhanced electrochemical performances of FeOx-graphene nanocomposites as anode materials for alkaline nickel-iron batteries

A new type of graphene-based FeOX nanocomposites have been synthesized by high temperature solidstate reaction using FeC2O4$ 2H(2)O. The synthesis conditions are optimized by thermogravimetric analysis of the precursor. When evaluated as anode material for the alkaline nickel-iron battery, the FeOxgraphene nanocomposites deliver a high specific capacity of 552.1 mA h g (-1) at a current density of 200 mA g(-1) and retain 91% of the initial capacity after 100 cycles. Furthermore, the hybridized FeOxgraphene materials undergo only 26% capacity decay when the discharge current density is changed from 200 mA g(-1) to 1000 mA g (-1) The enhanced cycling and high discharge rate performance derives from the high specific surface area of iron oxide nanoparticles and particular electric conductivity of graphene. This study suggests a safe, inexpensive and powerful rechargeable iron electrode, enabling the promising prospect of large-scale energy storage based on the aqueous iron-based rechargeable battery.