Room temperature liquefied petroleum gas (LPG) sensor

The p-polyaniline/n-ZnO thin film heterojunction sensor for room temperature LPG detection was fabricated by electrodepositing polyaniline on chemical bath deposited ZnO film. The heterojunction showed rectifying behavior indicating the formation of a diode with ideality factor 1.10. The formation of diffusion free interface of heterojunction was confirmed from cross-sectional FESEM. The heterojunction sensor has quick and high response towards LPG as compared to N2 and CO2 and exhibited maximum response of 81% upon exposure of 1040 ppm of LPG. The LPG sensing mechanism for heterojunction is modeled through change in height of barrier potential.