Performance Evaluation of Low-Cost Flexible Gas Sensor Array With Nanocomposite Polyaniline Films

The aim of this paper is to present the design of a sensor array based on a single substrate with various composite polymer films as active layers for gas detection. A low power, four element flexible sensor platform with heater and temperature sensor was designed. The advantages of resistive sensors are easy fabrication, simple operation, and low production cost. Composite polymer films exhibit good sensitivity to low gas concentrations at room temperatures. The principle of the designed sensor array is a change of electrical resistance in dependence of gas concentration. Polyaniline (PANI), PANI/carbon nanotubes, PANI/SnO ₂ , and PANI/TiO ₂ composites were used as active layers. Gas sensing properties of active layers for NH ₃ , CO ₂ , NO ₂ , O ₂ , acetone, toluene, and relative humidity were studied. PANI composites, unlike pristine PANI, exhibit good reversibility and lower temperature dependence.