Humidity and Ammonia Vapor Sensing Applications of Polyaniline–Polyacrylonitrile Composite Films

In the present paper, hydrochloric acid (HCl) and p-toluene sulphonic acid (p-TSA) doped polyaniline–polyacrylonitrile (PANI–PAN) composite films have been prepared, characterized and used as humidity and ammonia vapor sensing material. The change in resistivity of the composite films with respect to percent of relative humidity (%RH) was found to be decreased with increase humidity range from 20–90% by some order of magnitude, using four-probe technique. The composite films were also found to be possess significant ammonia vapor sensing capacity. The isothermal stability study in terms of DC electrical conductivity retention was also investigated. The results of some preliminary investigations regarding the humidity and ammonia vapor sensitivity are being reported here. These results are discussed in terms of potential applications of these composite materials.