Benzodithieno-imidazole based π-conjugated fluorescent polymer probe for selective sensing of Cu2+

Abstract

π-Conjugated polymers appended with binding sites are of considerable interest as an evolving new class of heavy and toxic metal ion sensors through fluorescence quenching. In this study we describe the synthesis and characterization of a p-bromophenyl substituted benzodithieno-imidazole based soluble and rigid π-conjugated polymer with N and S donors exhibiting outstanding sensitivity towards Cu²⁺ by emission quenching through photoinduced electron transfer (PET). Detailed photophysical and ion sensing studies have been demonstrated to understand insight of the polymer–metal ion interaction which is responsible for selective fluorescence quenching. The corresponding polymer is also explored as a thin-film polymeric sensor towards Cu²⁺ as monitored by a photoluminescence study.