Chae, Huijeong Han, Ji Min Ahn, Yejin Kwon, Ji Eon Lee, Wi Hyoung Kim, Bong-Gi 2024-01-19T13:32:05Z 2024-01-19T13:32:05Z 2022-01-10 2021-11 2365-709X https://pubs.kist.re.kr/handle/201004/116217 Three conjugated polymers (CPs) containing indolocarbazole-based similar conjugated frameworks are designed to investigate the NO2 detection capability of field-effect transistor (FET) sensors. The partly linear aliphatic side chain strengthens the crystallization tendency of the CPs, but the crystallinity is critically degraded when introducing an ethylene oxide (EO)-modified side chain to the same conjugated framework. Although the highly crystalline morphology of the CP helps to achieve high hole mobility, the NO2 response rate of the CP-based FET sensor is severely deteriorated because of the suppression of NO2 diffusion into the CP matrix. The polar and flexible EO-modified side chain is helpful to improve the NO2-affinity of the CPs and induce favorable pathways for NO2 diffusion, ultimately providing enhanced detectivity with better NO2-response characteristics. As a result, despite low charge carrier mobility due to pure amorphous nature, the CP with EO-modified side chains provides an exceptional sensitivity of 180%/ppm upon NO2 (100 ppb) exposure for 50 s, including distinct detectivity toward other environmentally abundant harmful polar gases, such as SO2, NO, and NH3. English WILEY NITROGEN-DIOXIDE AMMONIA PERFORMANCE MORPHOLOGY NO2-Affinitive Amorphous Conjugated Polymer for Field-Effect Transistor Sensor toward Improved NO2 Detection Capability Article 10.1002/admt.202100580 1 ADVANCED MATERIALS TECHNOLOGIES, v.6, no.11 ADVANCED MATERIALS TECHNOLOGIES 6 11 scie scopus 000678540600001 2-s2.0-85111134864 Materials Science, Multidisciplinary Materials Science Article NITROGEN-DIOXIDE AMMONIA PERFORMANCE MORPHOLOGY conjugated polymer distinct detection ethylene oxide side chain field effect transistor NO (2) sensor