Design and synthesis of a polymer for Cr(III) ions sensing

A fluorene and amino-based conjugated polymer (PFluDNH
2
) was designed to selectively detect chromium (III) ions. The synthesis of the sensing polymer molecules was achieved in four steps which involved the formation of a diamino intermediate and the polymerization of this intermediate with a fluorene derivative. The structural elucidation of the synthesized molecules was performed using FTIR, 1H-NMR, 13C-NMR, and UV-Vis spectroscopic techniques. The cyclic-voltammetric experiments were performed to examine the electrochemical properties. Optical properties were studied by the photoluminescence (PL) technique. Synthesized PFluDNH
2
displayed enhancement in fluorescence intensity upon selectively interacting with Cr (III) ions by showing chelation-enhanced fluorescent (CHEF) effect. The intensity increased after an excitation wavelength of 350 nm. The synthesized polymer showed good potential for metal ion detection and light-emitting devices.