Surface NMR experiment by a hyperpolarized molecular beam

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K21148
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 29:Applied condensed matter physics and related fields
• Research Institution: National Institute for Materials Science
• Principal Investigator: Kurahashi Mitsunori 国立研究開発法人物質・材料研究機構, 先端材料解析研究拠点, 主席研究員 (10354359)
• Co-Investigator(Kenkyū-buntansha): 後藤 敦 国立研究開発法人物質・材料研究機構, 先端材料解析研究拠点, グループリーダー (30354369)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: 表面 / 水素 / 核磁気共鳴 / 偏極ビーム

Outline of Final Research Achievements

NMR is known to be a powerful tool for analyzing chemical states of elements. Its application to the analysis of hydrogen on surfaces would provide valuable information on the surface chemical processes. However, detection of NMR signals from a sample with submonolayer thickness has been considered to be difficult due to the low sensitivity of the conventional NMR measurement. Hyperpolarization has attracted much attentions since it greatly enhances the intensity of the NMR signal. The purpose of the present study is to construct an instrument which allows us to irradiate a sample surface with a hyperpolarized molecular beam and detect the NMR signal from the polarized nucleus. A hyperpolarized molecular molecular beam generated with a use of a hexapole magnet was combined with an UHV NMR apparatus, and its performance was tested with bulk samples.

Free Research Field

表面科学、偏極ビーム

Academic Significance and Societal Importance of the Research Achievements

表面の水素原子の位置や化学状態の計測は、表面物性や多くの物理化学現象の理解に不可欠である。NMRは局所状態分析能が高く、様々な材料研究に応用されているが、感度が不十分のために表面分析への応用は極めて限定的で報告例はXeなど特殊な系に限られている。表面に存在する水素原子のNMR測定を実現できれば今後の表面水素研究の重要な手段となり得るが、この問題に挑戦するための実験装置を今回の研究を通じて製作することができた。