You are cordially invited to UNAM Seminars focusing on advancements in the field of nanoscience and nanotechnology. The seminars bring us the most recent developments in these exciting fields. This week’s talk will be presented by Prof. Myung-Han Yoon (Gwangju Institute of Science and Technology).
UNAM Seminars
Title: Highly Crystalline Organic Mixed Ionic-Electronic Conductors for Microfiber-Based Bioelectronic Interfaces and Energy Storage Devices
Date: March 12, 2026 (Thursday)
Time and Venue: 15:30 UNAM Conference Hall (SU-01)
Abstract:
In this research, we report highly crystalline organic mixed ionic-electronic conductors (OMIECs) designed to overcome the inherent trade-off between electrical/electrochemical performance and long-term aqueous stability. First, by introducing a sulfuric acid treatment, we successfully crystallized poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) films. These films exhibit excellent electrical, electrochemical, and optical properties, alongside robust long-term stability and high biocompatibility for primary cultured cardiomyocytes and neurons over several weeks. Consequently, they were successfully employed in high-performance multi-electrode arrays (MEAs) to record and stimulate the electrophysiological activities of primary cardiomyocytes and chicken retinal tissues. Furthermore, we developed the fabrication of crystalline PEDOT:PSS microfibers and a unique self-fusion process to create single-strand wearable electrochemical transistors and 3D microfibrillar network-based bioelectronic interfaces. Finally, we demonstrated fiber-type energy storage devices by implementing carbon nanotube (CNT) yarn/PEDOT:PSS core-shell fibers.
- Kim, S.-M., et al. Influence of PEDOT:PSS Crystallinity and Composition on Electrochemical Transistor Performance and Long-term Stability, Nature Communications, 9, 3858 (2018).
- Kim, Y., et al. Single Strand Microfiber-Based Wearable Human Sweat Sensors with Channel Dimension Independent Performance, NPG Asia Materials, 10, 1086 (2018).
- Kim, Y., et al. Strain-engineering Induced Anisotropic Crystallite Orientation and Maximized Carrier Mobility for High-performance Microfiber-Based Organic Bioelectronic Devices Adv. Mater. 33, 2007550 (2021).
- Saini, N.; Lee, D.-Y.; Yoon, M.-H., and Awasthi, K., Unveiling the Potential of Pt Nanoparticle-Decorated PEDOT:PSS Membranes for Efficient Gas Separation, ACS Applied Materials & Interfaces, 16, 7700 (2024).
- Kim, Y.*, et al. Arbitrary 3D Organic Mixed Ionic-Electronic Conductor Architectures via Self-Fusion of PEDOT:PSS Microfibers, Science Advance, e16951 (2025).
Short Bio:
Myung-Han Yoon earned his B.S. and M.S. in Chemistry from Seoul National University. He
subsequently received his Ph.D. in Inorganic/Materials Chemistry from Northwestern
University (2006) under the supervision of Profs. Tobin J. Marks and Antonio Facchetti,
focusing on high-performance organic semiconductor/dielectric thin-film transistors.
Following his doctoral studies, he completed a postdoctoral fellowship at Harvard University with Prof. Hongkun Park, where he specialized in the development of neuronal electronic and microfluidic interface arrays. In 2010, Dr. Yoon joined the Gwangju Institute of Science and Technology (GIST), where he currently serves as a Professor in the Department of Materials Science and Engineering. His professional leadership roles include serving as an Associate Editor for the Journal of Materials Chemistry B (Royal Society of Chemistry, UK) and an advisory professor for LG Electronics. With over 15,000 citations and an h-index of 51, his prolific research has earned prestigious recognitions, including Commendations from the Prime Minister (2024) and the Minister of Science and ICT (2019) of the Republic of Korea.
He is also a three-time recipient of the GIST Excellent Research Award (2016, 2022, 2025) and has been honored by the Polymer Society of Korea and the Korean Chemical Society.
His current research interests are at the forefront of functional and sustainable materials,
encompassing organic mixed ionic-electronic conductors (OMIECs), metal oxides, and
fibrillar hydrogels. These materials are applied toward bioelectronic interfaces, neuromorphic electronics, renewable energy (hydrogen generation), and advanced environmental purification.