Disentangling conduction pathways at the ionic-electronic interface in EMI-TFSI-covered graphene transistors

• 成果类型: Article
• 署名作者: Lizee, Mathieu; Esfandiar, Ali; Panoni, Eva; Mischenko, Artem; Taberna, Pierre-Louis; Simon, Patrice; Bocquet, Lyderic
• 署名单位: Max Planck Society; Fritz Haber Institute of the Max Planck Society; Universite Paris Cite; Universite PSL; Ecole Normale Superieure (ENS); Sharif University of Technology; University of Manchester; Centre National de la Recherche Scientifique (CNRS); CNRS - Institute of Chemistry (INC); Universite de Toulouse; Universite Federale Toulouse Midi-Pyrenees (ComUE); Universite Toulouse III - Paul Sabatier; Institut National Polytechnique de Toulouse
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-10126
• DOI: 10.1073/pnas.2426506122
• 发表日期: 2025-04-29
• 关键词: liquids; DYNAMICS

摘要

Transport of electrons and ions at carbon surfaces immersed in electrolytes is instrumental for a wide variety of membrane processes as well as energy storage in batteries and supercapacitors. Ion transport in a nanoporous electrode strongly depends on its electronic conductance and on the interfacial capacitance with the electrolyte. In this study, we use in-plane impedance spectroscopy to disentangle in-plane ionic and electronic transport on a single crystal graphene transistor covered by an ionic TFSI). droplet. Due to the atomic thickness of graphene combined to the strong affinity of EMI+ for carbon, this transistor maximizes ion-electron couplings. Using gate- and temperature-dependent in-plane spectroscopy, we extract both the electronic and ionic conductance of the transistor on a wide range of charge carrier density and over several decades of electrolyte conductivity. We show that despite an exceptionally high capacitive coupling at the carbon-EMI-TFSI interface, the ionic and electronic transport pathways are decoupled at the micrometric scale, in agreement with predicted lengthscales involved in the electronic-ionic interfacial transport.