Electrochemical behaviour of stand-alone polyaniline-poly(vinyl alcohol) composite films

In this report, we investigate the electrochemical capacitance and redox behaviour of a stand-alone polyaniline-poly(vinylalcohol) composite film cast on an insulating substrate (normal printer paper) and compared it with an electrochemically synthesized composite film deposited on a gold electrode. The stand-alone composite film showed timescale-dependent, wide range charging-discharging redox cycling and high electrochemical capacitance in potentiodynamic electrochemical experiments carried out in 1 M HCl solution. The stand-alone composite film exhibited two distinct current density responses during redox switching. This might be attributed to the different doping and de-doping modes, represented by ions trapped at deep and shallow levels in the bulk of the composite polymer film and the double layer of the modified electrode-electrolyte interface. The wider electrochemical window and higher capacitance response of the stand-alone film are important for battery technology and in energy storage and conversion devices. (C) 2014 Taibah University. Production and hosting by Elsevier B.V. All rights reserved.