Thermal Desorption of Explosives Vapour from Organic Fluorescent Sensors

Abstract

Organic semiconductors can be used as highly sensitive fluorescent sensors for the detection of trace-level vapours of nitroaromatic explosives. This involves fluorescence quenching of the sensors and indicates the presence of explosives in the surrounding environment. However, for many organic fluorescent sensors, the quenching of fluorescence is irreversible and imposes a limitation in terms of the reusability of the sensors. Here, we present a study of thermal desorption of 2,4-DNT from thin-film explosives sensors made from the commercial fluorescent polymers Super Yellow and poly(9-vinyl carbazole). Thermal cycling of the sensor results in recovery of fluorescence, thereby making them reusable.