An AIEgen-based fluorescence probe for ratiometric detection of phosgene in solution and gas

Phosgene, a toxic and asphyxiating gas, poses a significant threat to human health. In this study, a ratiometric fluorescence probe for phosgene detection was synthesized based on the combination of an aggregation-induced emission tetraphenylethylene (TPE) luminophore and rhodamine hydrazide. The probe exhibits a unique and sensitive response to phosgene based on its spirolactam ring-opening properties and nucleophilic reaction with phosgene. Notably, the probe exhibits a significantly enhanced Stokes shift of 103 nm for ratiometric phosgene detection. Additionally, test strips were developed for the detection of gas phosgene under 365 nm hand-held UV lamps. The design and synthesis of these molecules contribute significantly to environmental health and public safety.