Macromolecular Rapid Communications, Vol.34, No.5, 431-436, 2013
Near-Infrared Responsive Conjugated Polymers to 1.5 mu m and Beyond: Synthesis and Electrochromic Switching Application
Azulene-containing conjugated polymers with near-infrared absorption up to 1.5 m and beyond are achieved by treating with trifluoroacetic acid (TFA). Density functional theory calculations reveal that the near-infrared absorption arises from a strong intramolecular charge transfer transition on the polymer backbone, and the near-infrared absorption can be tuned by the degree of protonation. Furthermore, TFA treated polymers show a ten-fold enhancement in electrochromic contrast and significantly improved switching stability, suggesting that these polymers are promising candidates for fabrication of the first generation organic near-infrared devices.
Keywords:azulenes;charge transfer;conjugated polymers;density function theory;near-infrared absorptions