Molecular Dynamics Study of Morphology of Doped PEDOT: From Solution to Dry Phase.

Morphology of the conducting polymer PEDOT:TOS (poly(3,4-ethylenedioxythiophene) doped with molecular tosylate) and its crystallization in aqueous solution were studied using atomistic molecular dynamics simulations. It was found that (a) PEDOT comprises crystallite aggregates consisting of 3-6 π-π stacked chains. The crystallites are linked by interpenetrating π-π stacked chains such that percolative paths in the structure are formed. (b) The size of the crystallites depends on the water content, but the π-π stacking distance is practically independent of the chain length, charge concentration and water content.