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The development of polymeric thin films has attracted attention in the optoelectronics field due to their transparency. The aim of the research presented was to obtain transparent polyaniline thin films by easy in situ oxidative polymerization of aniline with ammonium persulfate in the presence of a binary doping agent-poly(vinyl alcohol) mixture. Poly(acrylic acid), 2-acrylamido-2-methyl-1-propanesulfonic acid or sodium dodecylsulfate were mixed with hydrochloric acid to form the binary doping agents. Polyaniline thin films were produced during aniline polymerization on Corning glass slides immersed in the mixture in order to study their optical, electrical and morphological properties. The optical absorption coefficient and the energy band gap were evaluated by optical transmission of the films in the UV-visible spectral region. The optical absorption coefficient of all polyaniline films was of the order of 10 4 cm −1 with a maximum transmittance up to 80% at 550 nm. In order to investigate the effect of the mixture on the surface morphology and roughness of the films, atomic force microscopy was used. In general, surface roughness was reduced threefold by adding a mixture and optical transmission was increased by 20-30% without significantly affecting the absorption coefficient and the band gap of polyaniline. Islands and needle-like structures on the film surfaces were obtained from various mixtures affecting the conductivity; for example, 0.17 S cm −1 was obtained from needle-like morphology, while 1.9 × 10 −4 S cm −1 was obtained from island morphology. Raman spectroscopy studies confirmed the presence of poly(vinyl alcohol) in the thin films.

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