Improving the electrical conductivity and electrochemical properties of PEDOT:PSS thin films by Ca and Mg doping

Abstract

Among the conductive polymers, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has advantages such as low cost, transparency and easy fabrication, but its heterogeneous structure presents limitations in terms of electrical conductivity. In this study, the electrical conductivity and electrochemical properties of PEDOT:PSS have been improved via use of Ca and Mg as doping materials. Electrical conductivity of undoped and 5 mg/mL Mg- and Ca-doped PEDOT:PSS films was calculated as 1.57 x 10(-2), 3.45 x 10(-2) and 4.68 x 10(-2) Scm(-1), respectively. Furthermore, Ca- and Mg-doped PEDOT:PSS thin films had wider area in comparison with undoped PEDOT:PSS thin films in cyclic voltammetry (CV) measurements for the determination of electrochemical properties. Higher polarization area clearly shows that doping of Ca and Mg has positive effects on capacitance of PEDOT:PSS, which might be attributed to the improving electron mobility after doped.