Characterization of PEDOT Films for Electrochromic Applications

Poly 3,4-ethylenedioxythiophene (PEDOT) films were formed on Indium Tin Oxide (ITO)-coated glass by electrodeposition. Cyclic voltammetry, AFM and UV-Vis spectroscopy were employed to investigate the properties of the PEDOT films. Two different types of PEDOT films, i.e., (i) smooth and homogenous surface with pinnacle-like structure and (ii) rough and nonhomogenous with grain-like structure) were produced in two ways. These included varying deposition times and by applying different deposition potentials. The surface roughness of the PEDOT films increased with increasing deposition time and applied potential used. The smooth film prepared at +1.1 V for 15 s has good electrochromicc and optical properties. However, its stability over repetitive usage is inadequate and needs further improvement.