POS5-1174
Simultaneous Enhancement of Hole Mobility and Volumetric Capacitance in PEDOT:PSS via proton conductor Induced Phase Separation for Biocompatible Low-Voltage OECTs
When and Where
Nov 30, -0001
00:00 - 00:00
Presenter(s)
JONGMIN LIM (Department of Materials Science and Engineering, Kookmin University, Seoul, Republic of Korea)
Co-Author(s)
Abstract
Due to their mixed conduction and biocompatibility, organic electrochemical transistors(OECTs) have emerged as key components in low-power bioelectronics and neuromorphic systems. However, while Faradaic gates exhibit less voltage drop, their fabrication process hinder high-density in-plane integration. Conversely, capacitive gates offer easier fabrication but suffer from interfacial voltage losses, whereas polymer coating strategies compromise process simplicity. Therefore, developing a device architecture that preserves fabrication ease while ensuring high responsiveness at low operating voltages is essential.
We present an OECT platform incorporating a proton electrolyte and a short-side-chain proton conductor-blended PEDOT:PSS channel. The optimized(1vol% proton conductor) device achieves max transconductance of 4.2±0.2mS, representing a 16.6-fold enhancement compared to a reference device utilizing a long-side-chain proton conductor(5wt%) and a BMIM:TFSI electrolyte. This enhanced performance is driven by the structural advantages of the short-side-chain, which provides a higher density of proton transport domains that increase ion injection. Its functional groups induce phase separation of PEDOT:PSS by weakening the electrostatic attraction between them. It makes hole transport and capacitance enhance. These proton conductor domains act as ion traps to regulate synaptic plasticity. The optimized device shows a current of tens to hundreds of µA, whereas reference device does at a few µA.
And then, we observed that as the proton conductor content increased from 1vol% to 10vol%, the intrinsic hole mobility of the polymer(µHole) increased from 0.219±0.050cm2V-1s-1 to 0.299±0.050cm2V-1s-1, whereas these during operation(µOECT) decreased from 0.150±0.036cm2V-1s-1 to 0.036±0.008cm2V-1s-1. To investigate this, we will use GIWAXS to compare each film's crystallinity during electrochemical doping.
We present an OECT platform incorporating a proton electrolyte and a short-side-chain proton conductor-blended PEDOT:PSS channel. The optimized(1vol% proton conductor) device achieves max transconductance of 4.2±0.2mS, representing a 16.6-fold enhancement compared to a reference device utilizing a long-side-chain proton conductor(5wt%) and a BMIM:TFSI electrolyte. This enhanced performance is driven by the structural advantages of the short-side-chain, which provides a higher density of proton transport domains that increase ion injection. Its functional groups induce phase separation of PEDOT:PSS by weakening the electrostatic attraction between them. It makes hole transport and capacitance enhance. These proton conductor domains act as ion traps to regulate synaptic plasticity. The optimized device shows a current of tens to hundreds of µA, whereas reference device does at a few µA.
And then, we observed that as the proton conductor content increased from 1vol% to 10vol%, the intrinsic hole mobility of the polymer(µHole) increased from 0.219±0.050cm2V-1s-1 to 0.299±0.050cm2V-1s-1, whereas these during operation(µOECT) decreased from 0.150±0.036cm2V-1s-1 to 0.036±0.008cm2V-1s-1. To investigate this, we will use GIWAXS to compare each film's crystallinity during electrochemical doping.
