Ultrasensitive Fluorescent Detection of Sarin Simulant Vapor via Micropit Array-Mediated Mass Transfer and Photonic Modulation

Gas-solid interface fluorescent sensors hold considerable promise for nerve agent vapor detection. However, their sensitivity is limited by insufficient analyte capture at active sites and inefficient utilization of excitation light. In this study, we demonstrate ultrasensitive detection of the sarin simulant diethylchlorophosphate (DCP) using a two-in-one micropit array (MPA) strategy that integrates vortex-driven molecular enrichment with excitation-light trapping. The sensor achieves an ultralow detection limit of 0.1 ppb for DCP. Furthermore, a fluorescent sensor array composed of 1@Pt@MPA and Aggregate-1@Pt@MPA is constructed to enable accurate discrimination between DCP and HCl when combined with machine learning algorithms. This study provides a facile, scalable, and general strategy for developing next-generation high-performance gas sensing systems and offers new structural and mechanistic insights for chemical warfare agent monitoring and environmental protection.