Proceedings of MATSUS Fall 2023 Conference (MATSUSFall23)
DOI: https://doi.org/10.29363/nanoge.matsus.2023.258
Publication date: 18th July 2023
The development of organic electrochemical transistors (OECTs) capable of maintaining their high amplification, fast transient speed, and operational stability in harsh environments will advance the growth of next‐generation wearable electronics, robotics and biological electronics. In this study, a high-performance solid-state OECT (SSOECT) is successfully demonstrated, showing a recorded high transconductance of 220 ± 59 S cm−1, ultrafast device speed of ≈10 kHz with excellent operational stability over 10 000 switching cycles, and thermally stable under a wide temperature range from −50 to 110 °C. The developed SSOECTs are successfully used to detect low-amplitude physiological signals, showing a high signal-to-noise-ratio of 32.5 ± 2.1 dB. For the first time, the amplifying power of these SSOECTs is also retained and reliably shown to collect high-quality electrophysiological signals even under harsh temperatures. The demonstration of high-performing SSOECTs and its application in harsh environment are core steps toward their implementation in next-generation wearable electronics and bioelectronics. We also will present our recent work on developing fibrous electrolyte containing polymer matrix and ionic liquid, which is highly robust, breathable, waterproof, and conformal with human skin is reported. Serving as fibrous substrate and electrolyte of OECTs, a high transconductance of ≈0.8 mS, stability over pulsing and time (≈1000 cycles and 30 days) are achieved. The softness of fibrous OECTs enables a comfortable contact after attaching to human skin, which can reduce the interfacial impedance to achieve a high-quality local amplification of the electrocardiography signals (signal-to-noise ratio of 21.7 dB) even in skin squeezed state or after one week. These results indicated that our fibrous OECTs have huge potential for versatile on-skin electronics such as non-invasive medical monitoring, soft sensors, and textile electronics.