Charge Carrier Induced Structural Ordering And Disordering in Organic Mixed Ionic Electronic Conductors
Artikel i vetenskaplig tidskrift, 2024

Operational stability underpins the successful application of organic mixed ionic-electronic conductors (OMIECs) in a wide range of fields, including biosensing, neuromorphic computing, and wearable electronics. In this work, both the operation and stability of a p-type OMIEC material of various molecular weights are investigated. Electrochemical transistor measurements reveal that device operation is very stable for at least 300 charging/discharging cycles independent of molecular weight, provided the charge density is kept below the threshold where strong charge–charge interactions become likely. When electrochemically charged to higher charge densities, an increase in device hysteresis and a decrease in conductivity due to a drop in the hole mobility arising from long-range microstructural disruptions are observed. By employing operando X-ray scattering techniques, two regimes of polaron-induced structural changes are found: 1) polaron-induced structural ordering at low carrier densities, and 2) irreversible structural disordering that disrupts charge transport at high carrier densities, where charge–charge interactions are significant. These operando measurements also reveal that the transfer curve hysteresis at high carrier densities is accompanied by an analogous structural hysteresis, providing a microstructural basis for such instabilities. This work provides a mechanistic understanding of the structural dynamics and material instabilities of OMIEC materials during device operation.

operando X-ray scattering

microstructural stability

organic semiconductors

electrochemical transistors

organic mixed conductors

Författare

Tyler J. Quill

Stanford University

Garrett LeCroy

Stanford University

Adam Marks

Stanford University

Sarah A. Hesse

Stanford Synchrotron Radiation Laboratory

Quentin Thiburce

Stanford University

Iain McCulloch

University of Oxford

Christopher J. Tassone

Stanford Synchrotron Radiation Laboratory

Christopher J. Takacs

Stanford Synchrotron Radiation Laboratory

Alexander Giovannitti

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Stanford University

Alberto Salleo

Stanford University

Advanced Materials

09359648 (ISSN) 15214095 (eISSN)

Vol. 36 15 2310157

Ämneskategorier

Den kondenserade materiens fysik

DOI

10.1002/adma.202310157

PubMed

38198654

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Senast uppdaterat

2024-04-20