Room temperature ammonia sensor based on electrodeposited polyaniline film

Polyaniline (PANI) is a conducting polymer which has been widely used during the last decades in (bio)sensing applications. In the present work, a solution of aniline, camphorsulfonic acid and fluoral-p has been formulated and used as electrolyte for the electrochemical deposition of a porous film of PANI at the surface of a flexible interdigitated sensor device. Then, the ability of the electrodeposited PANI film to detect reducing ammonia gas was studied in the range 50-200 ppb. The resulting PANI-based sensor device exhibited high sensitivity to ammonia, good repeatability, and reversible response in a broad range of relative humidity.