Detection and identification of explosives by surface enhanced Raman scattering

Abstract

Surface Enhanced Raman Scattering (SERS) has undergone an important development over the last few years, particularly in the detection and identification of extremely low traces of explosives. The large number of studies and results generated by this increasing research makes a comprehensive overview necessary. This work reviews in detail that research focused on the identification of explosives by SERS, including TNT, DNT, RDX, PETN, TATP, HMTD, perchlorate, etc. either in bulk state, in solution or in vapour phase. In brief, TNT and DNT have been widely studied by SERS due to its aromatic structure and LODs down to 5-10 zg and 10 -17 -10 -13 M have been achieved. The other explosives have been quite less researched; therefore, few results are available to be compared and a bit more modest LODs have been reached such as 10 -13 M for RDX, 10 -4 M for TATP, 5 pg for PETN, or 10 -9 M for perchlorate. In addition, the challenges of detecting both explosives vapours and perchlorate anion by SERS are thoroughly discussed. ExplosiveChemical structure Characteristic normal Raman bands (cm -1 ) SERS bands (cm -1 ) SERS substrate used LOD or minimum amount analysed in molar conc., mass or both Ref.

Detecting explosive molecules from nanoliter solution: A new paradigm of SERS sensing on hydrophilic photonic crystal biosilica

“…In addition, TNT is also widely used in underwater explosion and many other industrial applications, which could lead to the contamination of soil and ground water (Yang et al, 2010). A variety of technologies such as mass spectroscopy, photoluminescence (PL), chromatography and Raman spectroscopy (GrahamáCooks, 2005; Harvey et al, 1990; He et al, 2015; Zhen et al, 2016) are currently employed to detect TNT in the environment, among which surface-enhanced Raman scattering (SERS) is one of the most popular detection techniques (Dasary et al, 2009; Hamad et al, 2014; Jamil et al, 2015a, 2015b; Zapata et al, 2016). Although ultra-high detection sensitivity has been reported, surface functionalization of the SERS substrates sometimes are required and the Raman signals actually come from the probe molecules rather than TNT itself (Hakonen et al, 2015; He et al, 2015; Yang et al, 2010) because the binding affinity of TNT toward metallic nanoparticle surfaces is very low.…”

Recent Developments in Spectroscopic Techniques for the Detection of Explosives

“…In a recent review, the recognition of explosives in different states was summarized, the potential of SERS for vapor detection of explosives through SERS sensors as chemical noses was shown, and the problems of perchlorate anion detection in water was reviewed [121]. Hakonen et al discussed the possible use of SERS for convenient in-situ threat recognition and summed up existing SERS detection methods and substrates with a distinctive focus on ultra-sensitive real-time detection [122].…”

Surface Enhanced Raman Scattering Substrates Made by Oblique Angle Deposition: Methods and Applications

“…There has been a lot of research in the area of detecting explosive components/by-products [92,93], however, there is limited literature involving OAD derived SERS in this area [31]. The work done by Nuntawong et al have shown the use of oblique magnetron sputtering deposition, which in itself is rare.…”