Poly(3,4-ethylenedioxyselenophene) (PEDOS) prepared via electropolymerization was investigated as an active electrode material for supercapacitor in 0.1 M CH3CN-LiCIO4. Meanwhile, Poly(3,4-ethylenedioxythiophene) (PEDOT) as a contrast was prepared and measured under the same conditions. The resultant polymers were characterized by EQCM, FT-IR, SEM, CV and EIS. Although EDOS possessed higher molar mass which may result in lower specific capacitance in theory, but the higher doping level (y=0.53) make the specific capacitance of PEDOS over that of PEDOT. Based on this, PEDOS has the potential to become a good supercapacitor material. The compact PEDOS electrode afforded a higher specific capacitance of 208 Fr-1 at 25 mVs(-1) compared with PEDOT (205 Fg(-1)). Furthermore, the specific capacitance of the symmetric full cell based on two PEDOS electrodes reached 42.02 Fg(-1) at 25 mV s(-1). (C) 2016 Elsevier Ltd. All rights reserved.