Supercapacitive Studies on IrO[sub 2] Thin Film Electrodes Prepared by Radio Frequency Magnetron Sputtering

Ir O 2 thin films were prepared by radio frequency magnetron sputtering technique at different substrate temperatures. Supercapacitive properties of the films were studied by cyclic voltammetry and electrochemical impedance spectroscopy in 1 M Li N O 3 electrolyte for the first time. The specific capacitance of the single Ir O 2 film electrode was calculated to be 293 F g − 1 at a scan rate of 5 mV s − 1 for the sample prepared at room temperature. After 1000 cycles , the specific capacitance of Ir O 2 electrode decreases slightly, indicating the sputtered Ir O 2 thin-film electrode has excellent cycling performance in aqueous Li N O 3 electrolyte.