Cost effective nanostructured copper substrates prepared with ultrafast laser pulses for explosives detection using surface enhanced Raman scattering

Abstract

Ultrafast laser pulses induced surface nanostructures were fabricated on a copper (Cu) target through ablation in acetone, dichloromethane, acetonitrile, and chloroform. Surface morphological information accomplished from the field emission scanning electron microscopic data demonstrated the diversities of ablation mechanism in each case. Fabricated Cu substrates were utilized exultantly to investigate the surface plasmon (localized and propagating) mediated enhancements of different analytes using surface enhance Raman scattering (SERS) studies. Multiple utility of these substrates were efficiently demonstrated by collecting the SERS data of Rhodamine 6G molecule and two different secondary explosive molecules such as 5-amino-3-nitro-l,2,4-triazole and trinitrotoluene on different days which were weeks apart. We achieved significant enhancement factors of >105 through an easily adoptable cleaning procedure.

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.…”

Femtosecond Laser Fabricated Ag@Au and Cu@Au Alloy Nanoparticles for Surface Enhanced Raman Spectroscopy Based Trace Explosives Detection

“…Chen et al detected ammonium nitrate (AN) and RDX with EF of ∼7.0 × 10 4 using a monolayer of ordered Au NPs on Si substrates [23]. Our group has recently demonstrated the detection of several explosives such as picric acid (5 µM), AN (50 µM) using gold nanoparticles and nanostructures [13], ammonium perchlorate (10 µM) using Ag decorated Silicon nanowires [24], FOX-7 (5 µM) and 1NPZ (20 nM) [25], ANTA (1 µM) and TNT with E.F.'s >10 5 [26] using femtosecond laser fabricated NPs/NSs. Furthermore, we have also reported the detection of 2, 4-Dinitrotoluene using Ag-Au nanostructures achieved using femtosecond laser ablation [13].…”

Morphologically manipulated Ag/ZnO nanostructures as surface enhanced Raman scattering probes for explosives detection

“…The adsorption factor (g) was estimated following the Langmuir isotherm models 39,40 as described in our previous reports. 38,41 The detail of the adsorption factor calculation is reported in the supplementary material S3. 34 The area under the Raman peak centered around 1362 cm À1 has been chosen for EF calculation of ZnO/Ag samples annealed at 500 C for different morphologies (A to F), and the calculated values are 5 Â 10 8 , 1.5 Â 10 9 , 9.7 Â 10 8 , 3.1 Â 10 9 , 2.2 Â 10 9 , and 4.7 Â 10 8 , respectively.…”

“…These Raman modes are assigned to NO 2 deformation þ ring deformation (840 cm À1 ), ring deformation (1067 cm À1 ), N-N symmetric stretch (1120 cm À1 ), ring deformation þN-H bend (1283 cm À1 ), C-NO 2 symmetric stretch (1340 cm À1 ), and C-N symmetric stretch (1459 cm À1 ). 38 The strong Raman peak in the vicinity of 1340 cm À1 has been selected for EF calculation for ANTA molecule, and the values for different morphologies (A-F) are 9.6 Â 10 6 , 3.3 Â 10 7 , 7.1 Â 10 7 , 2.6 Â 10 7 , 1.7 Â 10 7 , and 5.4 Â 10 7 , respectively. In comparison, the EF was only 1.1 Â 10 4 for the Ag nanostructures on BSG.…”