Stretchable, Enhancement-Mode PEDOT:PSS Organic Electrochemical Transistors

Stretchable organic electrochemical transistors (OECTs), based on the conducting polymer poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate) (PEDOT: PSS), have shown significant potential in bridging the gap between microelectronic devices and the soft biological environment [1,2]. However, there has been a lack of corresponding stretchable devices that can operate in enhancement mode, which has limited the development of low-power soft integrated circuits and systems.<br/><br/>In our research, we present the first stretchable PEDOT: PSS OECTs that operate in enhancement mode. This achievement is made possible by the development of two key elements: A straightforward solution-based method that efficiently removes dopants from stretchable PEDOT: PSS thin films; A two-step soft annealing process that immobilizes the de-doping agents on the transistor's channel without affecting its functionality.<br/><br/>Experimental results have demonstrated that the combination of these two approaches allows for the creation of robust and stretchable enhancement-mode OECTs. These devices can be stretched between 0% and 50% strain and remain functional even after repeated stretching tests. These stretchable enhancement-mode PEDOT: PSS OECTs are expected to serve as new building blocks for the development of low-power organic biosensing and bioelectronics systems.<br/><br/>[1]. Zhang, Shiming, et al. "Patterning of stretchable organic electrochemical transistors." <i>Chemistry of Materials</i> 29.7 (2017): 3126-3132.<br/>[2]. Bai, Jing, et al. "Tissue-like organic electrochemical transistors." <i>Journal of Materials Chemistry C</i> 10.37 (2022): 13303-13311.