In this work, a cross-linked sheet structured conducting polymer ploy(3,4-ethylenedioxythiophene) (PEDOT) decorated on Ni foam is synthesized via one-step electrodeposition using the sodium p-toluenesulfonate (STSA) as surfactant and applied for supercapacitor electrode. The surfactants play a vital role in controlling the morphologies of PEDOT leading to the electrochemical performance difference. The optimized PEDOT electrode exhibits the highest capacitance of 711.6 mF cm(-2) at 3.0 mA cm(-2) in the three electrode system. An asymmetric device (PEDOT/STSA//AC) is constructed by PEDOT/STSA (the positive electrode), activated carbon (AC) (the negative electrode) as well as 1 M Na2SO4 (the electrolyte). The device has been worked in a high-voltage range of 0-1.5 V, which displays the satisfied energy density of 14.0 Wh.kg(-1) at 535.5 W kg(-1). Furthermore, the PEDOT/STSA//AC device presents excellent rate capability and long-time cyclic stability. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.