Combination of phosphonium and ammonium pendant groups in cationic conjugated polyelectrolytes based on regioregular poly(3-hexylthiophene) polymer chains

•Polythiophene-based polyelectrolytes were prepared by simple quaternization reaction.•Polyelectrolytes with ammonium and phosphonium pendant groups were synthesized.•The effect of phosphonium and ammonium pendants on optical properties was assessed.•Fluorescence quenching by model pollutants was investigated using the Stern-Volmer method.