Gravure printed flexible surface enhanced Raman spectroscopy (SERS) substrate for detection of 2,4-dinitrotoluene (DNT) vapor

An efficient surface enhanced Raman spectroscopy (SERS) substrate was successfully fabricated by gravure printing a thin film of silver nanoparticle (Ag NP) ink, with average particle size of 150 nm, on flexible polyethylene terephthalate (PET) sheet. The feasibility of the printed SERS substrate for detecting explosive organic compounds such as 2,4-dinitrotoluene (DNT), in vapor phase, was investigated. The SERS based response of the printed substrate demonstrated an enhancement factor of four in the intensity of the Raman signal of DNT vapor when compared to target molecules adsorbed on bare PET. An 85% decrease in the intensity of the Raman spectrum was also observed as the temperature increased from 25 °C to 65 °C. The results obtained show the efficiency of the gravure printed SERS substrate to be used in applications for the detection of explosive organic compounds.