A conductive polymer, polyaniline (PANI), was easily prepared on an electrode surface as a stable film by the electropolymerization of aniline in acidic solution. In McIlvain’s buffer solution with a pH that exceeded 4, no redox current by the dissolved species was observed on the PANI-modified electrode because PANI acted as an electric insulator. However, in a less acidic solution, the redox current of the dissolved hydroquinone was evident because hydroquinone selectively permeates through the PANI film to reach the electrode substrate. The results of steady-state current-potential curves for the oxidation of hydroquinone using a PANI pellet electrode revealed that hydroquinone was concentrated in the PANI during the electro-oxidation. Furthermore, the concentration of hydroquinone increased the electric conductivity of the PANI from 6.50×10-7 S/cm to 2.73×10-3 S/cm.
electrodeposition, less acidic solution, polyaniline, hydroquinone, conductivity.
Financial support by the Ogasawara Foundation for the Promotion of Science & Engineering is gratefully acknowledged.
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