Vertical Growth Dynamics and Multifractality of the Surface of Electropolymerized Poly(o-ethoxyaniline) Thin Films

Abstract

Electropolymerized poly(o-ethoxyaniline) (POEA) nanostructured thin films were successfully deposited on indium tin oxide (ITO) substrate. The surface dynamic of the films was extensively investigated using morphological and multifractal parameters extracted from the atomic force microscopy (AFM). AFM topographical maps reveal surfaces with different morphologies as a function of the deposition cycles. The height parameters show that there is greater spatial vertical growth for films deposited with higher cycles of deposition. After five cycles of deposition occurs the formation of a more isotropic surface, while for 15 cycles a less isotropic surface is observed. The Minkowski functionals confirm that morphological aspects of the two films change according to the amount of deposition cycles employed. The POEA surfaces also exhibit a strong multifractal nature with a decrease in the multifractal spectrum width as the number of deposition cycles increases. Our findings prove that deposition cycles can be useful in controlling the vertical growth and surface dynamics of electropolymerized POEA nanostructured samples, which can be useful for improving the fabrication of POEA-coated ITO-based devices.