Abstract
A key challenge in the development of organic mixed ionic-electronic conducting materials (OMIEC) for high performance electrochemical transistors is their stable performance in ambient. When operating in aqueous electrolyte, potential reactions of the electrochemically injected electrons with air and water could hinder their persistence, leading to a reduction in charge transport. Here, the impact of deepening the LUMO energy level of a series of electron-transporting semiconducting polymers is evaluated, and subsequently rendering the most common oxidation processes of electron polarons thermodynamically unfavorable, on organic electrochemical transistors (OECTs) performance. Employing time resolved spectroelectrochemistry with three analogous polymers having varying electron affinities (EA), it is found that an EA below the thermodynamic threshold for oxidation of its electron polarons by oxygen significantly improves electron transport and lifetime in air. A polymer with a sufficiently large EA and subsequent thermodynamically unfavorable oxidation of electron polarons is reported, which is used as the semiconducting layer in an OECT, in its neutral and N-DMBI doped form, resulting in an excellent and air-stable OECT performance. These results show a general design methodology to avoid detrimental parasitic reactions under ambient conditions, and the benefits that arise in electrical performance.
| Original language | English (US) |
|---|---|
| Article number | 2403911 |
| Journal | Advanced Materials |
| Volume | 36 |
| Issue number | 44 |
| DOIs | |
| State | Published - Nov 1 2024 |
Funding
The authors acknowledge financial support from KAUST Office of Sponsored Research CRG10, by EU Horizon2020 grant agreement n\u00B0 952911, BOOSTER, grant agreement n\u00B0862474, RoLA-FLEX, and grant agreement n\u00B0101007084 CITYSOLAR, as well as EPSRC Projects EP/T026219/1, EP/W017091/1, and EP/L011972/1. C.E.T. acknowledges support from the Royal Society through grant URF\u2216R1\u2216201071. For the purpose of Open Access, the author has applied a CC BY public copyright license to any Author Accepted Manuscript (AAM) version arising from this submission. K.S. and J.-S.K. acknowledge the UK EPSRC for funding through both the ATIP Programme Grant (EP/T028513/10) and the Plastic Electronics Centre for Doctoral Training (EP/L016702/1), and the Imperial College High Performance Computing Service for DFT calculations. This work utilized the Keck-II facility of Northwestern University's NUANCE Center and Northwestern University Micro/Nano Fabrication Facility (NUFAB), which are both partially supported by the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205), the Materials Research Science and Engineering Center (NSF DMR-1720139), the State of Illinois, and Northwestern University. Additionally, the Keck-II facility is partially supported by the International Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois through the II. H.Y.W. acknowledges the financial support from the National Research Foundation of Korea (2019R1A6A1A11044070. This publication is based upon work supported by King Abdullah University of Science and Technology Research Funding (KRF) under Award No. ORA-2021-CRG10-4650. The authors acknowledge financial support from KAUST Office of Sponsored Research CRG10, by EU Horizon2020 grant agreement n\u00B0 952911, BOOSTER, grant agreement n\u00B0862474, RoLA\u2010FLEX, and grant agreement n\u00B0101007084 CITYSOLAR, as well as EPSRC Projects EP/T026219/1, EP/W017091/1, and EP/L011972/1. C.E.T. acknowledges support from the Royal Society through grant URF\u2216R1\u2216201071. For the purpose of Open Access, the author has applied a CC BY public copyright license to any Author Accepted Manuscript (AAM) version arising from this submission. K.S. and J.\u2010S.K. acknowledge the UK EPSRC for funding through both the ATIP Programme Grant (EP/T028513/10) and the Plastic Electronics Centre for Doctoral Training (EP/L016702/1), and the Imperial College High Performance Computing Service for DFT calculations. This work utilized the Keck\u2010II facility of Northwestern University's NUANCE Center and Northwestern University Micro/Nano Fabrication Facility (NUFAB), which are both partially supported by the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS\u20101542205), the Materials Research Science and Engineering Center (NSF DMR\u20101720139), the State of Illinois, and Northwestern University. Additionally, the Keck\u2010II facility is partially supported by the International Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois through the II. H.Y.W. acknowledges the financial support from the National Research Foundation of Korea (2019R1A6A1A11044070. This publication is based upon work supported by King Abdullah University of Science and Technology Research Funding (KRF) under Award No. ORA\u20102021\u2010CRG10\u20104650.
Keywords
- electron affinity
- in situ electrochemical resonant Raman spectroscopy
- organic electrochemical transistors
- semiconducting polymers
- time-resolved spectroelectrochemistry
ASJC Scopus subject areas
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering