Ion transport in poly(3,4-ethylenedioxythiophene)-poly(styrene-4-sulfonate) composites

The ion transport properties and electrochemistry of both chemically prepar ed and electrochemically prepared poly(3,4-ethylenedioxythiophene)-poly(sty rene-4-sulfonate) composites have been investigated by cyclic voltammetry a nd impedance spectroscopy in a variety of electrolyte solutions. The polyme rs exhibited facile electrochemistry, fast ion transport, and good electroc hemical stability. The ionic conductivities of the polymers are strongly de pendent on the concentration and conductivity of the electrolyte solution u sed. At low electrolyte concentrations, the ionic conductivities of these p olymers also show some potential dependence. Ion transport in chemically pr epared layers was found to be much faster than in electrochemically prepare d films. The high ionic conductivities of the polymers are shown to be due to their very porous structure and electrolytes in pores.