Role of aggregates and microstructure of mixed-ionic-electronic-conductors on charge transport in electrochemical transistors
Artikel i vetenskaplig tidskrift, 2023

Synthetic efforts have delivered a library of organic mixed ionic-electronic conductors (OMIECs) with high performance in electrochemical transistors. The most promising materials are redox-active conjugated polymers with hydrophilic side chains that reach high transconductances in aqueous electrolytes due to volumetric electrochemical charging. Current approaches to improve transconductance and device stability focus mostly on materials chemistry including backbone and side chain design. However, other parameters such as the initial microstructure and microstructural rearrangements during electrochemical charging are equally important and are influenced by backbone and side chain chemistry. In this study, we employ a polymer system to investigate the fundamental electrochemical charging mechanisms of OMIECs. We couple in situ electronic charge transport measurements and spectroelectrochemistry with ex situ X-ray scattering electrochemical charging experiments and find that polymer chains planarize during electrochemical charging. Our work shows that the most effective conductivity modulation is related to electrochemical accessibility of well-ordered, interconnected aggregates that host high mobility electronic charge carriers. Electrochemical stress cycling induces microstructural changes, but we find that these aggregates can largely maintain order, providing insights on the structural stability and reversibility of electrochemical charging in these systems. This work shows the importance of material design for creating OMIECs that undergo structural rearrangements to accommodate ions and electronic charge carriers during which percolating networks are formed for efficient electronic charge transport.

Författare

Garrett LeCroy

Stanford University

Camila Cendra

Stanford University

Tyler J. Quill

Stanford University

Maximilian Moser

University of Oxford

Rawad Hallani

King Abdullah University of Science and Technology (KAUST)

James F. Ponder Jr

UES Inc.

Air Force Research Laboratory

Kevin Stone

Stanford University

Stephen D. Kang

Stanford University

Allen Yu-Lun Liang

Stanford University

Quentin Thiburce

Stanford University

Iain McCulloch

King Abdullah University of Science and Technology (KAUST)

University of Oxford

Frank C. Spano

Temple University

Alexander Giovannitti

Stanford University

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Alberto Salleo

Stanford University

Materials Horizons

2051-6347 (ISSN) 2051-6355 (eISSN)

Vol. 10 7 2568-2578

Ämneskategorier

Oorganisk kemi

Fysikalisk kemi

Transportteknik och logistik

Annan kemi

DOI

10.1039/d3mh00017f

PubMed

37089107

Mer information

Senast uppdaterat

2024-03-07