Analysis of electric double layer at solid/solid electrolyte interfaces

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05279
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 29020:Thin film/surface and interfacial physical properties-related
• Research Institution: National Institute for Materials Science
• Principal Investigator: TSUCHIYA Takashi 国立研究開発法人物質・材料研究機構, 国際ナノアーキテクトニクス研究拠点, 主幹研究員 (70756387)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 固体イオニクス / 電気二重層 / ナノイオニクス

Outline of Final Research Achievements

The electric double layer (EDL) effect at solid electrolyte/electrode interfaces has been attracting attention for energy and nanoelectronics applications. However, characteristic of the EDL effect for solid electrolyte is not clear and its characterization remains difficult in comparison with liquid electrolytes.In this study, we used a novel method to investigate the EDL effect and found that the EDL effect, and its suppression at solid　electrolyte/electronic material interfaces, can be characterized on the basis of the electric conduction characteristics of H-diamond-based EDL transistors(EDLTs). Whereas H-diamond-based EDLT with a Li-Si-Zr-O Li+ solid electrolyte showed EDL-induced hole density modulation, EDLT with a Li-La-Ti-O (LLTO) Li+ solid electrolyte showed negligible enhancement, which indicates strong suppression of the EDL effect. Such suppression is attributed to charge neutralization in the LLTO, which is due to variation in the valence state of the Ti ions present.

Free Research Field

固体イオニクス

Academic Significance and Societal Importance of the Research Achievements

本研究で取り扱う固体電気二重層は，近年全固体電池やキャパシタなどのエネルギーデバイスの出力性能と密接に関係するため，本研究はこれらの高性能化に向けた研究開発，特に界面エンジニアリングにおいて重要な役割を果たし得る．本研究によって得られた固体電気二重層の解析手法はリチウム電解質に限らず幅広い固体材料に適用可能であるため，今後様々なエネルギーデバイスの研究開発において活用されるものと期待する．