Synthesis, photophysical and electrochemical properties of carbazole-containing 2, 6-quinoline-based conjugated polymer

Donor–acceptor-type conjugated polymers (CV-QP-1 and CV-QP-2) containing carbazole–quinoline moiety were polymerized via Wittig condensation route. The structure of the polymers was well established by FTIR, NMR and gel permeation chromatography (GPC) techniques. The two polymers exhibited UV–Vis absorption bands at around 250–340 nm in solution and 360–365 nm in thin film. Fluorescence spectra showed PL maximum at 390–460 nm in solution and 470–480 nm in thin film. They had thermal stability up to 225 °C with 7 % weight loss and char yields at 400 °C. The polymers showed irreversible oxidation with ionization potential ranging from 6.36 to 6.35 eV and reversible electrochemical reduction with electron affinity of 3.75–3.70 eV, which indicated that the polymers are expected to provide enhanced charge-transporting (electron transport/hole blocking) properties for the development of efficient polymer light-emitting diodes (PLEDs). Carbazole- and quinoline-functionalized polymer exhibits excellent metal ion detection towards Fe2+ which suggests that the synthesized polymers are expected to promise future application in metal ion sensing.