Design of sensor setup and study of humidity sensing behaviour of conducting polyaniline / ceramic composites

Sensor setup for the measurement of humidity was designed using square glass chamber provided with sample holder, vaporizer, hygrometer and temperature display. Using this set up, authors have studied the response time of the sensor setup and humidity sensing properties for Polyaniline (PANI) and PANI/sodium metavanadate (NaVO₃) composites. The variation in electrical resistance with change in relative humidity (RH) in the range between 20 to 95% of RH is reported and this may be due to change in surface electrical resistance. The variation in resistance and hence conductivity depends on capillary condensation of water causing ionic conductivity within the sensing materials.