Synthesis of novel materials in an electronically-stimulated nanogap

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K20552
• Research Category: Grant-in-Aid for Challenging Research (Pioneering)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 28:Nano/micro science and related fields
• Research Institution: Osaka University
• Principal Investigator: Yoshida Hideto 大阪大学, 産業科学研究所, 准教授 (00452425)
• Project Period (FY): 2020-07-30 – 2024-03-31
• Keywords: ナノギャップ / 電子顕微鏡 / 原子スケールその場観察 / 電界蒸発

Outline of Final Research Achievements

We succeeded in visualizing the phenomenon in which the surface structure of the biased gold, palladium, and platinum nanogap electrodes changes at atomic scale in gases by environmental transmission electron microscopy. The atomic arrangement on the electrode surface was disordered, and the atoms moved from the positive electrode to the negative electrode via field evaporation. We observed the phenomenon in which nanostructures of oxides and nitrides form and disappear on the nanogap electrode surface. Through simulations of the electric field and surface charge formed near the tip of a nanogap electrode, we found that the atomic and molecular dynamics on the nanogap electrode surface are correlated with the electric field strength.

Free Research Field

電子顕微鏡、ナノ材料、構造解析、その場観察

Academic Significance and Societal Importance of the Research Achievements

２つの電極からなるナノメーターサイズの空隙（ナノギャップ）にガス中で電圧を印加した際に起こる現象を環境制御型透過電子顕微鏡による直接観察とシミュレーションにより調べた。電極表面の構造が電界強度と気体種と気体圧力に依存して変化する現象や、酸化物や窒化物のナノ構造の形成過程を原子スケールで観察した。本研究により得られた成果は、ナノギャップ電極における電子と気体分子との反応メカニズムの解明と、新規ナノ材料の開発に繋がる。