Self-assembled polyaniline nanostructures with photoisomerization function

Nanostructures (e.g., nanotubes and nanofibers) of polyaniline (PANI) with an average diameter of 110-130 nm and a conductivity of 2.5 x 10(-2) S/cm were synthesized by a self-assembly process in the presence of azobenzenesulfonic acid (ABSA) as a dopant. It was found that the formation probability and size of PANI-ABSA nanostructures depended on the molar ratio of aniline to ABSA and the concentration of ABSA. ABSA or aniline-ABSA salt micelles were proposed to interpret the formation of PANI-ABSA nanostructures. In particular, the PANI-ABSA nanostructures exhibited trans-cis photoisomerization similar to that of the azobenzene moiety upon irradiation with UV light (lambda = 365 rm).