A UV-visible reflectance and transmission spectroelectrochemical study of the redox behavior of thin films of a sulfonated polyaniline derivative, poly(aniline-co-N-propanesulfonic acid aniline) (PAPSAH) and of a mixture of this same derivative and 2,5-dimercapto-1,3,4-thiadiazole (DMcT) is reported. The study shows the differential spectral changes that accompany the oxidation of PAPSAH, which comprise increases in the polaron band at 400 nm and a band at 600 nm. The reduction process of PAPSAH, comprises decreases in these same spectral bands. These changes are shown to be reversible with potential. For the case of the PAPSAH/DMcT mixed film, the data also reveal spectral changes that are characteristic of oxidation of DMcT to produce a disulfide polymer during PAPSAH oxidation. These changes are also reversible with potential. These data represent the first direct, spectroscopic observation of the redox mediation between a polyaniline derivative and DMcT.
sulfonated polyaniline; redox mediation; DMcT; lithium batteries
