POS5-0872
Decoupling Ionic Accessibility and Electronic Energetic Disorder in Organic Mixed Ionic-Electronic Conductors
When and Where
Nov 30, -0001
00:00 - 00:00
Presenter(s)
Jaehoon Lee (SKKU Advanced Institute of Nanotechnology (SAINT) and Department of Nano Science and Tecknology, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do 440-746, Korea)
Co-Author(s)
Abstract
Organic mixed ionic–electronic conductors (OMIECs) bring together rapid bulk ion movement and dependable electronic conduction, but the common route to better ionic access—incorporating polar side chains—tends to push those polar units into the well-ordered regions responsible for carrier transport, degrading electrical conduction. Building a separate polar network through crosslinking can raise ion transport without touching the conjugated backbone, yet its effect on the balance between the two carrier types has stayed unclear. We examine this here with chain-length-tuned nitrene-based photocrosslinkers (n-NIPS) incorporated into indacenodithiophene–benzothiadiazole (IDTBT), a high mobility conjugated polymer with poor ionic conductivity. Phase-selective segregation keeps the n-NIPS network within the amorphous free volume, laying down predefined ionic channels of adjustable length while leaving the ordered aggregates—and IDTBT's exceptionally narrow energetic distribution—intact. Time-resolved organic electrochemical transistor data, interpreted with a Chapman–Richards growth analysis, quantify the effect: crosslinking suppresses the microstructural rearrangement from ion penetration once its length surpasses the ion's dimension and decouples electronic conduction from the progressive deterioration characteristic of untreated films. Cyclic spectroelectrochemistry traces this stability to mechanical damping of microstructural rearrangement, which limits irreversible interchain disruption and broadens the reversible doping range. The work points toward a mechanism-guided strategy for low-disorder OMIECs in neuromorphic and bioelectronic applications.
