Quantum Dot-Doped Electrospun Polymer Fibers for Explosive Vapor Sensors

Abstract

This research seeks to support reconnaissance efforts against homemade explosives (HMEs) and improvised explosive devices (IEDs), which are leading causes of combat casualties in recent conflicts. The successful deployment of a passive sensor to be developed for first responders and military must take expense, training requirements, and physical burden all into consideration. By harnessing the size-dependent luminescence of quantum dots (QDs) being electrospun into polymer fibers, the authors of this work hope to progress toward the development of lightweight, multivariable, inexpensive, easy to use and interpret, field-applicable sensors capable of detecting explosive vapors. The data demonstrate that poly(methyl methacrylate) (PMMA), polystyrene (PS), and polyvinyl chloride (PVC) fibers doped with Fort Orange cadmium selenide (CdSe) QDs, Birch Yellow CdSe QDs, or carbon (C) QDs will quench in the presence of explosive vapors (DNT, TNT, TATP, and RDX). In all cases, the fluorescent signal of the doped fiber continuously quenched upon sustained exposure to the headspace vapors. The simple method for the integration of QDs into the fibers' structure combined with their straightforward visual response, reusability, and durability all present characteristics desired for a field-operable and multimodal sensor with the ability to detect explosive threats.

Colloidal Quantum Dots for Explosive Detection: Trends and Perspectives

“…In 2021, Tawfik et al demonstrated the possibility to detect TATP in solution with polythiophene-capped CdTe CQDs, achieving a competitively low detection limit of 0.055 mg L –1 in water; the proposed device relied on an OFF-ON mechanism where the CQD PL was first quenched upon exposure to Hg 2+ ions via electron transfer, and then the PL recovery was induced by the addition of TATP to the solution. Ennis et al published a proof-of-concept study on the realization of a field-applicable sensor by electrospinning CdSe CQDs into polymer fibers and measuring the PL quenching upon exposure toward different kinds of explosive vapors including TATP and RDX, even if with very low efficiency with respect to nitroaromatic compounds . Although promising, these results need to be confirmed in validation studies.…”