Selective nano-devices for the detection of nitroaromatic explosive compounds

In recent years, there is an increased threat of explosive attacks worldwide, as the explosive - based weapons are easy to make, obtain and deploy. Detecting traces of explosives is a challenging task because of the low vapor pressures of most explosives [1]. Protecting against explosive-based terrorism can be achieved by large-scale production of nano-sensor arrays that are inexpensive, highly sensitive and selective with low response and recovery times. In the present study, we demonstrated the selective response of GaN nanowire/ TiO₂ nanocluster hybrids to the nitroaromatic explosive, Trinitrotoluene at room temperature. The sensor detected between 0.5 ppb and 8 ppm TNT with good selectivity against interfering compounds like Toluene. The sensitivity of 1 ppm of TNT is ~10% with response and recovery times of ~30 s.