Micromorphology and microtexture evaluation of poly(o-ethoxyaniline) films using atomic force microscopy and fractal analysis

Abstract

The morphology and microtexture of poly(o-ethoxyaniline) thin films deposited on the ITO substrate by electrodeposition were investigated. Cyclic voltammetry and FTIR were used to characterize the molecular structure, while Atomic Force Microscopy (AFM) technique was applied to obtain topographical images. The images were analyzed using commercial and free software. Moreover, three new parameters such as surface entropy, fractal succolarity, and fractal lacunarity were evaluated using recently developed theoretical models. The results showed that the morphology was affected according to the deposition cycles, while the analysis of the molecular structure indicated an increase in the polymer’s conjugation, mainly from 5 to 15 cycles. Structures related to the growth of poly(o-ethoxyaniline) were observed due to the increase in the number of deposition cycles. However, films did not grow completely. The microtexture was homogenized as the number of cycles increased. Furthermore, topographical uniformity was high for all films. Percolation remained low for all films, showing that although the formation of films was not completed, the microtexture of the material tended to homogenize as the film grew. These results revealed that the used tools can quantify the surface parameters, which are of great interest for the study of the corrosive properties of polymeric thin films.