PEDOT Composite with Ionic Liquid and Its Application to Deformable Electrochemical Transistors

Abstract

Organic electrochemical transistors (OECTs) have become popular due to their advantages of a lower operating voltage and higher transconductance compared with conventional silicon transistors. However, current OECT platform-based skin-inspired electronics applications are limited due to the lack of stretchability in poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). Some meaningful structural design strategies to resolve this limitation, including rendering OECT to make it more stretchable, have been reported. However, these strategies require complicated fabrication processes and face challenges due to the low areal density of active devices because wavy interconnect parts account for a large area. Nevertheless, there have been only a few reports of fully deformable OECT having skin-like mechanical properties and deformability. In this study, we fabricated stretchable and conductivity-enhanced channel materials using a spray-coating method after a composite solution preparation by blending PEDOT:PSS with several ionic liquids. Among these, the PEDOT composite prepared using 1-butyl-3-methylimidazolium octyl sulfate exhibited a better maximum transconductance value (~0.3 mS) than the other ion composites. When this material was used for our deformable OECT platform using stretchable Au nanomembrane electrodes on an elastomer substrate and an encapsulation layer, our d-ECT showed a barely degraded resistance value between the source and drain during 1000 cycles of a 30% repeated strain. We expect that our d-ECT device will serve as a step toward the development of more precise and accurate biomedical healthcare monitoring systems.

Electrochemical Doping and Dedoping Behaviors of PEDOT-Based Ternary Conducting Polymer Composites with Binary Polymer Surfactants

“…A hydrophobic nature and relatively large size of the TFSI anion presumably reduced its ability to influence the doping state of PEDOT. To our surprise, the PEDOT:PSS:PVS composites with a larger PVS ratio (over 30%) exhibited additional doping for a negative V G . − When a negative gate potential was applied, the composite films with 30% or more of PVS showed an increase in absorption in the NIR region (see bottom of Figure a). We believe that this observation is also related to the ion channel formed from PSS:PVS blends.…”

Boosting the Performance of PEDOT:PSS Based Electronics Via Ionic Liquids

“…[ 113 ] Moreover, Lee and co‐workers also harnessed spray‐coating technology to create a stretchable PEDOT:PSS composite film infused with ILs on an SEBS substrate, functioning as channel materials for deformable electrochemical transistor (d‐ECT) channel, which could undergo cyclic stretching within a designated strain range. [ 161 ] In general, OECTs with both flexibility and biocompatibility can fit perfectly with the skin, making them ideal wearable/implantable/sustainable and stable high‐performance electronic devices.…”

A high-performance PEDOT:PSS platform electrochemical biosensor for the determination of HER2 based on carboxyl-functionalized MWCNTs and ARGET ATRP

“…Poly (3,4-ethylenedioxythiophene (PEDOT) has been widely used in biosensors, 16 electrochemical transistors, 17 conductive coating, 18 solar cells 19 and other fields due to its excellent electrical conductivity, 20 biocompatibility 21 and environmental stability. 22 As a dopant, poly (4-styrenesulfonate) (PSS) is often mixed with PEDOT to improve the solubility and processability of the polymer.…”