In-situ analysis of atomic and molecular dynamics by high speed and high resolution measurement

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K15446
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 29020:Thin film/surface and interfacial physical properties-related
• Research Institution: Kyushu University
• Principal Investigator: Aso Ryotaro 九州大学, 工学研究院, 准教授 (40735362)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 環境制御型透過電子顕微鏡 / その場観察 / ダイナミクス / 電解蒸発 / 電界放射

Outline of Final Research Achievements

This study reports an in situ environmental transmission electron microscopy technique that allows changes in the atomic dynamics of a metal surface in a strong electric field to be visualized directly over time and under ambient conditions. In particular, the physical changes resulting from the oxidation of a gold electrode by oxygen atoms were tracked as the reaction progressed. We applied an electric field across a very small gap between gold electrodes, which activated the oxygen gas molecules present in the atmosphere by extremely fast electron tunneling. This in turn led to progressive changes at the surface of the gold electrodes--generally thought of as inactive--that we were able to clearly capture in images. This is the first reported direct visualization of progressive atomic changes of a metal surface in an electrostatic field under ambient conditions and has been termed a tunneling-electron-attached-gas process.

Free Research Field

電子顕微鏡学

Academic Significance and Societal Importance of the Research Achievements

本研究成果は、実環境中で動作中の金属ナノギャップ電極表面の連続的な原子変化を直接可視化した初めての報告であり、トンネル電子とガス分子との反応メカニズムである「トンネル電子付着ガスプロセス」という新たな反応メカニズムが解明された。このトンネル電子付着ガスプロセスが、ナノ触媒や量子ナノドットといった新たなナノ材料の設計・開発につながると期待される。