Highly Flexible and Conductive Glycerol-Doped PEDOT:PSS Films Prepared Under an Electric Field
Poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) films doped with several sugar alcohols, viz. xylitol (XL), glycerol (GL), and polyglycerol (PG), at various levels have been synthesized and their thermoelectric properties studied. Among these specimens, 2.5 vol.% GL-doped films showed the best performance with electrical conductivity σ, Seebeck coefficient S, and power factor S2σ at room temperature reaching 1040 S/cm, 19 μV/K, and 37 μW/m-K2, respectively. Next, we synthesized films under an electric field Epr for the purpose of crystal growth. GL-doped films showed σ enhancement with increase of Epr. The highest σ value of 1300 S/cm was attained at Epr = 4 kV/cm. S and thermal conductivity κ values were almost independent of Epr. The ZT value was calculated to be between 0.017 and 0.101 at room temperature. We also examined film flexibility. High flexibility was achieved on GL doping, and it was not deteriorated when synthesized under an electric field.