The sensing element of chemiresistive type sensors normally comprises of a
semiconducting material with high surface-to-volume ratio on a ceramic (glass) substrate
with ohmic contacts to measure the change in resistance/conductance. When, gas/volatile
organic compounds(VOC) samples interact on the surface of metal oxide semiconductor,
due to the combustion reaction that occurs with the oxygen species on the surface of
metal oxide particlesleads to change in resistance and forms the basic principle of
detection.