Organic Conjugated Polymers (Polypyrrol) based sensors for detection of hazardous gases

C. D. Marathe

Volume : V, Issue : XI, November - 2015

Organic Conjugated Polymers (Polypyrrol) based sensors for detection of hazardous gases

C. D. Marathe

Abstract :

Organic conjugated polymers (conducting polymers) have emerged as potential candidates for electrochemical sensors. Due to their straightforward preparation methods, unique properties, and stability in air, conducting polymers have been applied to chemical sensors. Polypyrrole (Ppy) was synthesized using Ferric Chloride (FeCl3) as an oxidants. The ratio of monomer to oxidants was 1: 2.4 and polymerization was carried out at room temperature. Attempts were made to increase the electrical conductivity by using Para–toluene Sulfonate (p–TS) as a dopants. The electrical conductivity was measured by two probe method was found to be in the range of 10–3 to 10–2 S/cm. Thin films of these preparations were casted on the interdigited electrodes to study the detection of ammonia gas. It was found that for the virgin Ppy, when ammonia gas was allowed to flow in there was a sudden increase in the current, which decreased rapidly when gas was stopped. However when doped Ppy was used, the trend was reversed.