Examining the use of TiO₂ to enhance the NH₃ sensitivity of polypyrrole films

Abstract

Abstract Polypyrrole/Titanium dioxide (PPy/TiO 2 ) composite thin films were prepared by polymerizing the monomer pyrrole in aqueous solution containing a certain amount of TiO 2 particles at room temperature, and their response to ammonia (NH 3 ) gas was examined systematically. Compared with the pristine PPy film, which reached the saturation at the concentration of NH 3 beyond 200 ppm, the composite films showed more stable response and higher sensitivity. Furthermore, the PPy/TiO 2 composite thin films exhibited a low detection limit of 2 ppm. The film thickness, which had a strong influence on the film sensitivity to NH 3 , could be controlled by varying the polymerization time. The sensitivity to NH 3 gas of the samples with different content of TiO 2 and different molar ratio of PPy/TiO 2 /oxidant was studied. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010