Research Progress on Fluorescent Probes for Detecting Phosgene: Mechanism, Reaction, and Performance.

Phosgene is a highly toxic chemical warfare agent that continues to pose a serious threat to public health and safety, thereby creating a strong demand for rapid, sensitive, and reliable onsite detection methods. Among currently available analytical approaches, fluorescent probes offer distinct advantages, including high sensitivity, high selectivity, fast response, and operational simplicity, which make them particularly attractive for phosgene monitoring. This review summarizes small-molecule fluorescent probes for phosgene detection with well-defined sensing mechanisms reported since 2020. Particular emphasis is placed on the fundamental relationships among response mechanism, reaction type, fluorophore architecture, and recognition site. On this basis, a mechanistic framework integrating sensing mechanism, reaction pathway, and analytical performance is proposed to clarify the structure-property relationships underlying successful probe design. It is anticipated that this review will provide a useful reference for the rational design of next-generation and high-performance fluorescent probes for phosgene detection.