Flexible camphor sulfonic acid-doped PAni/α-Fe2O3 nanocomposite films and their room temperature ammonia sensing activity

Abstract

Composite nanostructures play a crucial role in gas sensing applications owing to their tunable properties and sizes. The main goal of this article is to prepare camphor sulfonic acid (10–50 wt%)-doped PAni/α-Fe2O3 (PFC) composite nanostructured films on flexible polyethylene terephthalate (PET) substrate through in-situ polymerization process and study their gas sensing activity towards various gases. Structural and morphological measurements along with gas sensing properties in terms of selectivity, response, stability, and response-recovery times are investigated and reported. The gas selectivity tests of flexible PFC nanostructured composite films are performed towards different gases such as NO2, NH3, LPG, CH3OH, and C2H5OH etc., wherein all the flexible PFC (10–50%) films demonstrate a superior selectivity towards NH3 gas even in the presence of other test gases. Among the different compositions, 30% PFC flexible film exhibits highest response of 72% to 100 ppm NH3 with good response time of 65 s. The systematic study between PFC flexible nanocomposite films and NH3 gas is conducted and reported. In addition, the interfacial charge transfer kinetics across NH3 and PFC film interface was investigated by means of impendence spectroscopy study.