abstract |
Using thin-films of iron oxide as the active material of electrodes, supercapacitors are fabricated on various substrates in different shapes. By chemical oxidation the iron-oxide film is formed directly and conformably on the substrates in a short period of cooking. The iron oxide has a chemical composition of Fe x O y H z , where 1.0≦x≦3.0, 0.0 ≦y≦4.0, and 0.0≦z≦1.0. Substrates, as the current collector, tested includes Al, Ti, Fe, Cu and Ni. Measurements by cyclic voltammetry indicates that the iron-oxide electrodes in a selected electrolyte can store charges as high as 0.5 F/cm 2 or 417 F/g of the electrode materials. Supercapacitors as prepared are economical and can be used as enclosure housings for portable electronics, power tools, and batteries. The supercapacitors can also be integrated with the frames and chassis of electric vehicles. |