The Detection Of Explosives By Raman Spectroscopy Technology

With the increasing of terrorist activities and environmental problem, people now are tending to pay more and more attention to the personal safety and environmental protection field. A method which can detect explosives systematically and rapidly is currently needed. It has been demonstrated that Raman spectroscopy shows high sensitivity in detecting trace explosives, so in this paper, we detect explosives by Raman spectroscopy. The mains contents are listed as follows:1) We detected the mainly ingredients of the explosives (RDX, TNT, HMX, CL-20, PETN, AP, AN, TATB) by Raman spectroscopy and assigned the vibrational mode of the explosives by the method of quantum computation. Some judgments were presented for determining whether the tested sample was explosives or not based on the test results. The nondestructive sample preparation and the sensitivity of detection made the Raman spectroscopy as an ideal tool for detecting the explosives.2) A "hotspots" controllable surface enhanced Raman scattering (SERS) was prepared by self-assemble technique whose structure was that the surface of glass slides assembled Ag nanoparticles (AgNPs) arrays. In order to optimize the SERS substrate, we compared the morphology of the assembled AgNPs and the soak time of the glass slides immersed into the Ag colloid, respectively. The substrate was examined by UV-Vis absorption spectrometer, transmission electron microscopy, field emission scanning electron microscopy. We could get a high quality Raman spectra by using this SERS substrate, and the limit detection concentration was as low as 0.01 mg/L. This low-cost, ultra-high sensitivity, facile-manipulation of the sample preparation made the SERS spectroscopy a rapid and powerful on-site instrument in trace detection of explosives.3) Because of the metamorphosis of AgNPs assembled on the glass slides as SERS substrate, we fabricated a portable and easy to store SERS substrate. The transmission electron microscopy and UV-vis absorption spectrometer were used to characterizing the substrate. By using this substrate, the trace levels of common explosives have been successfully measured. This portable, sensitivity, reliability and wide spectrum detection provided a basis on rapid, on-site detection of explosives.