Poly[3-(butylthio)thiophene] Langmuir-Blodgett films as selective solid state chemiresistors for nitrogen dioxide

Films of poly[3-(butylthio)thiophene] were prepared via Langmuir-Blodgett (LB) deposition for applications in gas sensor devices. A description of the LB deposition of the sensing layer starting from a mixture of polymer and arachidic acid is given. Alumina substrates equipped with gold interdigitated electrodes have been used. In particular, the samples so prepared show variation in the electrical conductivity when exposed to NO² oxidising agent at a working temperature of about 80 °C. Selectivity towards NO² with respect to other different gases like ammonia, carbon monoxide, ethanol, methanol and methane has been evaluated.