Fluorescence Detection of a Broad Class of Explosives with One Zinc(II)-Coordination Nanofiber

In this work, we report the development of one fluorescent carbazole-based oligomer 1-zinc(II) coordination nanofiber which enabled the detection of five classes of explosives, i.e., nitroaromatics (dinitrotoluene, DNT, and trinitrotoluene, TNT), aliphatic nitro-organics (2,3-dimethyl-2,3-dinitrobutane, DMNB), nitramines (cyclotrimethylenetrinitramine, RDX), nitro-esters (pentaerythritol tetranitrate, PETN), and black powder (sulfur). We demonstrate that the coordination of zinc ion with a carbazole-based oligomer 1 allows the formation of the Lewis acid-base complex between explosives and the nanofiber that enhances the electron-accepting ability of the nitro-based explosives and the binding interactions between the sensing nanofibers and explosives. Furthermore, the resulting nanofiber-based sensor exhibited highly sensitive fluorescence quenching when exposed to trace sulfur, thereby enabling the sensitive detection of black powder. Herein, we present a new fluorescent sensor for five classes of explosives, which represents an important advance toward a richer identification of threats.