Synthesis and application of carbowax/polypyrrole nanocomposite for fabrication of electrochemical sensor to detect 2,4-DNT vapor

• Published in: Materials research express 2017-08, Vol.4 (8), p.86303
• Main Authors: Koudehi, Masoumeh Foroutan, Pourmortazavi, Seied Mahdi
• Format: Article
• Language: English
• Subjects: 2,4-dinitrotoluene; carbowax; electrochemical sensors; polypyrrole nanoparticles
• ISSN: 2053-1591; 2053-1591
• DOI: 10.1088/2053-1591/aa804a

In this study, an electrochemical sensor coated with carbowax/polypyrrole nanocomposite was fabricated so as to be sensitive to 2,4-dinitrotoluene (2,4-DNT) as a nitroaromatic explosive. The variation in electrical resistance was used as the mechanism by which the sensor responded to the concentration of explosive vapor. Polypyrrole (PPy) nanoparticles were synthesized and characterized using a scanning electron microscope (SEM), ATR-FTIR (attenuated total reflection Fourier transform infrared) spectroscopy and x-ray diffraction analysis (XRD). The results showed that the fabricated PPy nanoparticles have a near spherical morphology with an average size of around 56 nm. The surface of the sensor template was then coated with a layer of nanocomposite composed of the synthesized PPy nanoparticles and carbowax polymer. Calibration and performance testing of the fabricated sensors were carried out with a special setup designed for explosive vapor generation under static conditions. The developed sensor was able to sense different concentrations of the explosive (0.5-100 ppm). The coated sensor showed a linear response in the concentration range of 0.5-50 ppm. The results showed that the designed sensor had a favorable sensitivity to the explosive. The calibration curve and sensitivity of the fabricated carbowax/PPy sensor was also determined in the explosive vapor concentration range of 0.5-50 ppm of 2,4-DNT under static conditions.