Preparation and characterization of vacuum deposited semiconducting nanocrystalline polymeric thin film sensors for detection of HCl

• Published in: Polymer (Guilford) 2004-11, Vol.45 (25), p.8623-8628
• Main Authors: Misra, S.C.K., Mathur, Prafull, Yadav, Maneesha, Tiwari, M.K., Garg, S.C., Tripathi, P.
• Format: Article
• Language: English
• Subjects: Application fields; Applied sciences; Copolymer; Exact sciences and technology; Nanocomposite; Polymer industry, paints, wood; Semiconducting; Technology of polymers
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2004.10.010

Detection and monitoring of hazardous species like HCl, by fast, simple, cost effective, highly specific and selective devices is the main issue for environmental scientists. The currently available detection methods are either indirect or time consuming and expensive. These sensors are operated at high temperatures and response time is very slow. The nanocomposite polymeric combinations have come out as efficient sensors for detection of hazardous gases. Nanocomposite copolymers of aniline and formaldehyde synthesized by chemical polymerization with metal complex of Fe–Al have been found to act as high selective and efficient sensors for HCl. Thin films of Fe–Al doped nanocomposite copolymer evaporated under high vacuum on various substrates like mica and glass have been found to exhibit high stability, sensitivity, selectivity and a fast response towards the presence of HCl vapors in the air. High stability, sensitivity, selectivity and specificity are obtained by optimization of doping (Fe–Al) in nanocomposite copolymer during synthesis. These sensors operate at room temperature. The preparation, optical, electrical, and structural characterization and behavioral acceptance test on the gas sensing properties of these sensors are reported here.