Capacitive performance of the composite electrodes consisted of polyaniline and activated carbons powder in a solid-like acid gel electrolyte

Composite electrodes for surpercapacitors were fabricated by depositing polyaniline (PAn) on the surface of activated carbon powders (ACP) by using the electrochemical method. Their capacitance values were measured in the 1 M H2SO4 aqueous electrolytes containing SiO2, which showed the conductivity values of 2.6 x 10(-1), 2.3 x 10(-1), and 1.5 x 10(-1) S/cm for their liquid, gel, and solid-like gel states, respectively, according to the content Of SiO2. The Pt/ACP/PAn electrodes showed a specific capacitance value of 270 F/g in the 1 M H2SO4 solid-like electrolyte, which value was larger than the capacitances of 144 and 209 F/g for the Pt/ACP and the Pt/PAn, respectively. This result suggests that the capacitance performance of the ACP can be improved by compositing with PAn, and the 1 M H2SO4 solid-like electrolyte is suitable for the use in the supercapacitor. (C) 2004 Elsevier Ltd. All rights reserved.