Diffusion through the self-affine surface of polypyrrole film

•Fractal dimension is calculated using electrochemical methods and AFM images.•Results obtained by electrochemistry showed more complexity than AFM images.•Diffusion through the surface of PPy has self-affine scaling property.

The fractal dimension of the surface of Poly Pyrrole (PPy) film was calculated using Atomic Force Microscopy (AFM) images, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods. The results obtained by electrochemical methods showed more chaotic behavior than the AFM image because some parts of porous structure were not accessible to imaging devices. Since the values obtained from electrochemical methods are based on a diffusing process, comparing the values of fractal dimension obtained from SEM images and electrochemical methods showed that a diffusing process through the PPy film presents self-affine scaling property.