A compact wireless gas sensor using a carbon nanotube/PMMA thin film chemiresistor

The design and development of a compact wireless gas sensor with a surface modified multiwalled carbon nanotube (f-CNT) chemiresistor as the sensing element is presented in this paper. f-CNT/polymer composite sensing film is patterned on a printed circuit board and is integrated to the wireless system. The change in resistance of the CNT/polymer composite film due to exposure of different gases is utilized as the principle of this gas sensor. The response for different organic vapors are evaluated and it is observed that the f-CNT/PMMA composite film shows fast response and change in resistance of the order of 10(2)-10(3) due to its surface modification.