Guest Lecture | A Blend Strategy for Multifunctional Organic Electrochemical Transistors
Featuring Gitti L. Frey, professor of materials science and rngineering at the Technion – Israel Institute of Technology
Guest lecture featuring Gitti L. Frey, professor and former dean of materials science and engineering at the Technion – Israel Institute of Technology
Title: A Blend Strategy for Multifunctional Organic Electrochemical Transistors
Abstract:
Organic electrochemical transistors (OECTs) are versatile devices used in bioelectronics, energy storage, mechanical actuators, and sensors, relying on organic mixed ionic-electronic conductors (OMIECs) to modulate bulk conductivity through ion injection and extraction from an electrolyte. Recently, we introduced a novel design strategy for OECTs by blending p-type and n-type OMIECs, enabling enhanced performance and multifunctionality. By tailoring the blend microstructure through composition and thermal treatments, we control phase separation, crystallinity, and domain morphology to optimize ionic and electronic conductivity, as well as ionic-electronic coupling. This approach led to the development of fully balanced ambipolar OECTs, capable of modulating both anions and cations within a single device. Additionally, we extended this blend strategy to enable dual-operation functionality, where a p-type semiconducting polymer and an n-type OMIEC combine to create a device that operates as both an Electrolyte-Gated Organic Field-Effect Transistor (EGOFET) and OECT. In the p-type EGOFET regime, polymer-rich domains promote fast surface charge accumulation, while OMIEC-rich domains facilitate high amplification in the OECT n-type mode. This dual-operation mechanism allows for seamless transitions between the two modes. Our findings present a new framework for designing multifunctional, tunable organic transistors with enhanced ionic-electronic coupling, offering a promising platform for next-generation bioelectronics and advanced sensing applications.
Bio
Prof. Gitti L. Frey is a Professor and former Dean of Materials Science and Engineering at the Technion – Israel Institute of Technology. Her research focuses on organic semiconductors, with an emphasis on understanding and engineering the structure–property relationships that govern charge transport, injection, and collection in organic electronic devices. She leads a multidisciplinary effort to develop advanced materials and processing strategies for organic solar cells (OSCs), organic field-effect transistors (OFETs), and organic electrochemical transistors (OECTs). As the leader of The Science & Engineering of Organic Electronics Group, Gitti utilizes a broad range of characterization techniques to explore processes such as charge injection, transport, collection, and interfacial phenomena within these devices. Prof. Frey has held visiting positions at Colorado school of Mines, Georgia Tech, and NREL. She has authored over 80 peer-reviewed publications, holds several patents, and serves on the editorial boards of RSC and ACS journals. Her scientific and educational contributions have been recognized with awards including the Kavli Fellowship, the Yanai Award for Excellence in Academic Education, and repeated honors for teaching excellence at the Technion.