The Polymer Society of Korea

Abstract

 Organic semiconductors are susceptible to oxidation, leading to low air stability that hinders their commercialization in devices like sensors. in this study, we addressed this critical limitation by fabricating organic gas sensors with primary or secondary antioxidants added to the poly(3-hexylthiophene)(P3HT) active layer. The addition of these antioxidants significantly enhanced stability, effectively extending the device lifespan. In a 14 days stability test under extreme humidity, devices mixed with primary antioxidants showed a maximum on/off ratio retention about 6.2 times higher than the pristine devices, demonstrating excellent performance in delaying initial oxidation. Devices mixed with a secondary antioxidant proved to have long-term oxidation retardation. The antioxidant-added sensors also improved upon the low sensitivity and selectivity of conventioal organic gas sensors. This is due to the functional groups of the antioxidants interacting with NO₂ molecules.