Microscopical Investigations of PEDOT:PSS Thin Films

Abstract Electron microscopy studies are used to explore the morphology of thin poly(3,4‐ethylenedioxythiophene) and polystyrene sulfonate acid (PEDOT:PSS) films. The figures show that the films are composed of grains with diameters in the range of about 50 nm. Energy dispersive X‐ray spectroscopy analysis reveals that individual grains have a PEDOT‐rich core and a PSS‐rich shell with a thickness of about 5–10 nm. Atomic force microscopy (AFM) is then used to analyze the topography of fracture surfaces of ruptured PEDOT:PSS tensile specimens. These AFM scans also show that the films are composed of grains dispersed in a matrix. The investigations presented herein yield a picture of PEDOT:PSS morphology with unprecedented clarity.