Conjugated and fluorescent polymer based on dansyl-substituted carbazole: Investigation of electrochromic and ion sensitivity performance

Abstract

Fluorescent conjugated polymers have been used as excellent optical sensing materials to develop high sensitive and selective sensors by using their large extinction coefficient and high fluorescence quantum yield. Thanks to these features, conjugated polymers are used in a wide range of applications, including metal ion sensing and detection. In this study, a dansyl-substituted fluorescent polycarbazole was synthesized by electrochemical polymerization of 9H-carbazol-2-yl 5-(dimethylamino)naphthalene-1-sulfonate (CZD). CZD was characterized by 1H-NMR, FT-IR, UV-vis and fluorescence spectroscopy. Optical and electrochemical properties of polymer (PCZD) were investigated by voltammetric, spectroelectrochemical, kinetic studies and colorimetry measurements. Polymer showed a reversible electrochromic behavior from green to light yellow color. Moreover, the sensitivities of CZD toward metal cations were examined by observing the change in the fluorescence intensity. CZD was found to be selective toward Zn2+ with significant quenching emission intensity while the other metal ions did not show any interaction with CZD. This novel monomer CZD can be used as metal ion sensor, besides PCZD used in good electronic and optical applications.