Raman spectroelectrochemical study of self-doped copolymers of aniline and selected aminonaphthalenesulfonates

Novel self-doped polyaniline-like copolymers have been prepared by electrochemical copolymerization of aniline with four aminonaphthalenesulfonates. All copolymer films prepared show their electrochemical redox activity even in pH-neutral solutions at a midpoint potential around 0.0 V versus Ag/AgCl. Raman spectroelectrochemical study of the copolymers prepared has been done with a red laser excitation (632.8 nm) within a broad electrochemical potential window of 0.0–1.0 V, and specific Raman features have been identified. Raman bands within the range of 1300–1400 cm−1 have been discussed regarding localized or delocalized polaronic νs(CN+) vibrations. The influence of sulfonate group position in aminonaphthalenesulfonates on the parameters of polaronic bands has been demonstrated.