Transport properties of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate)

The conductivity and magnetoresistance of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDT/PSS) have been studied as a function of temperature. The room-temperature conductivities are dependent on the pH of the solutions from which the films are cast; values as high as 20 S/cm can be obtained in films cast from solutions with pH values in the range 0–3. The temperature dependence of the electrical conductivity is characteristic of granular metals (strongly disordered inhomogeneous systems), σ(T) = σ0exp[−(T0T)12]. The low-temperature magnetoresistance of PEDT/PSS is positive and follows an H2 dependence at low magnetic fields.