Preparation and Supercapacitive Properties of Fe2O3/Active Carbon Nanocomposites

G633.8; Abstract Fe2O3/active carbon(Fe2O3/AC) nanocomposites were readily fabricated by pyrolyzing Fe3+ impregnated active carbon in a nitrogen atmosphere.The as-prepared composites were studied by X-ray powder diffraction(XRD),X-ray photoelectron spectroscopy(XPS) and transmission electron microscopy(TEM).The capacitive property of the composites was investigated by cyclic voltammetry(CV) and galvanostatic charge-discharge test.Physical characterizations show that the γ-Fe2O3 fine grains dispersed in the AC well,with a mean size of 21.24 nm.Electrochemical tests in 6 mol/L KOH solutions indicate that the as-prepared nanocomposites exhibited improved capacitive properties.The specific capacitance(SC) of Fe2O3/AC nanocomposites was up to 188.4 F/g that was derived from both electrochemical double-layer capacitance and pseudo-capacitance,which was 78％ larger than that of pristine AC.A symmetric capacitor with Fe2O3/AC nanocomposites as electrode showed an excellent cycling stability.The SC was only reduced by a factor of 9.2％ after 2000 cycles at a current density of 1 A/g.