Highly fluorescent triazolopyridine–thiophene D–A–D oligomers for efficient pH sensing both in solution and in the solid state

Abstract

Triazolopyridine–thiophene fluorophores exhibit high fluorescence quantum yields both in solution (80–89%) and in the solid state (13–26%). Because of an excellent and reversible pH induced fluorescence quenching/recovery, sensing devices such as fluorescent papers and complex inkjet-printed patterns are successfully fabricated for the detection of volatile acids both in solution and in a vapor atmosphere.