Synthesis and characterization of porous flowerlike ?-fe2o3 nanostructures for supercapacitor application

Porous flower-like α-Fe2O3 nanostructures synthesized by an ethylene glycol mediated self-assembly process are crystalline and porous with BET surface area of 64.6 m2 g?1. The discharge capacitance is 127 F g?1 when the electrodes are cycled in 0.5 M Na2SO3 at a current density of 1 A g?1. Capacitance retention after 1000 cycles is about 80% of the initial capacitance. The high discharge capacitance and its retention are attributed to high surface area and porosity of the iron oxide. As the iron oxides are inexpensive, the nano ?-Fe2O3 is expected to be of potential use for supercapacitor application.