Choline Based Ionic Liquid for Re-Shaping Bioelectronics

As one of conducting polymers, PEDOT:PSS is commonly used in organic electronics, especially for bioelectronics due to its advantages such as high electrical and ionic conductivity, solution-processability and biocompatibility. Creating bioelectronics, for example organic electrochemical transistors (OECT), with the PEDOT:PSS requires advanced techniques to obtain physical/chemical modification of the PEDOT:PSS for improved performance and various applications.[1,2] To satisfy these demands, we demonstrated shape controllable gelation of PEDOT:PSS by injection to choline acetate, an ionic liquid, with a constant flow rate was used in this study to make a conductive fibers for textile OECT.[3] Conductive fibers by fibrillary gelation showed enhanced electrical conductivity of about 400 S cm⁻¹ and volumetric capacitance of about 154 F cm⁻³ which would be strongly beneficial to be utilized for organic OECTs, resulting in a high transconductance of 19 mS in a depletion-mode. Moreover, high performance of enhancement-mode OECTs could be demonstrate by dedoping. [4] These results demonstrate that these conductive fibers and electronic-textiles are suitable candidates for applications in bio-integrated electronics.

Reference
[1] Y.J. Jo, J. Ok, S.Y. Kim, and Tae-il Kim*, "Stretchable and Soft Organic-Ionic Devices for Body-Integrated Electronic Systems" Adv. Mater. Technol. 7 (2), 200123 (2022)
[2] Y.J. Jo, H. Kim, J. Ok, Y.-J. Shin, J.H Shin, T.H. Kim, Y. Jung and Tae-il Kim*, "Biocompatible and Biodegradable Organic Transistors using a Solid-State Electrolyte incorporated with Choline based Ionic Liquid and Polysaccharide" Adv. Funct. Mater. 30 (29) 1909707 (2020)
[3] Y.J. Jo, S.Y. Kim, J.H. Hyun, B. Park, S. Choy, G.R. Koirala, and Tae-il Kim*, "Fibrillary gelation and dedoping of PEDOT:PSS fibers for interdigitated organic electrochemical transistors and circuits", npj Flex. Electron. 6, 31 (2022)
[4] S. Choy, Y.J. Jo, et. al, Unpublished