The influence of electron beam irradiation on the electrochemical properties of electrodeposited RuO2 thin films was investigated using a 1 MeV electron beam. Crystallinity change before and after electron beam irradiation was investigated by X-ray diffraction, and the oxidation state of ruthenium was determined by X-ray photoelectron spectroscopy. Scanning electron microscopy was utilized to examine the morphology of the films. The results show that electron beam irradiation altered the oxidation state of ruthenium and increased crystallinity. Cyclic voltammetry was employed to evaluate the electrochemical properties of the synthesized RuO2 films in terms of their application as electrodes of electrochemical capacitors. RuO2 irradiated with 40 kGy showed 2.7 times higher capacitance (520 Fg(-1)) than the as-electrodeposited sample (190 Fg(-1)). (C) 2011 Elsevier B.V. All rights reserved.