TITLE:
Synthesis of Polypyrrole Using Ammonium Peroxy Disulfate (APS) as Oxidant Together with Some Dopants for Use in Gas Sensors
AUTHORS:
Hemant K. Chitte, Narendra V. Bhat, Mr. Ajit V. Gore, Ganesh N. Shind
KEYWORDS:
Polypyrrole, Structure, Doping, Gas Sensor, Ammonia
JOURNAL NAME:
Materials Sciences and Applications,
Vol.2 No.10,
October
18,
2011
ABSTRACT: Polypyrrole (Ppy) was synthesized using Ammonium Peroxy Disulfate (APS) as oxidant in a standard ratio of monomer to oxidants at 5℃. Attempts were made to increase the electrical conductivity by using various dopants viz. Lithium per Chlorate (LiClO4), para-Toluene Sulfonate (p-TS) and Napthalene Sulfonic acid (NSA). The materials were characterized using FTIR, X Ray diffraction and SEM. The electrical conductivity was measured by two probe method and was found to be in the range of 10-3 S/cm. Thin films of these preparations were casted on the interdigited electrodes to study the detection of gas such as ammonia. It was found that for the pure 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 Ppy doped with p-TS, NSA and LiClO4, the trend was reversed.