【公開日：2025.06.10】【最終更新日：2025.04.16】

課題データ / Project Data

課題番号 / Project Issue Number

24QS0104

利用課題名 / Title

Structural Identificition of NiFe-based Dual-Atom-catalysts by Synchrotron Radiation Moessbauer Spectroscopy

利用した実施機関 / Support Institute

量子科学技術研究開発機構 / QST

機関外・機関内の利用 / External or Internal Use

外部利用/External Use

技術領域 / Technology Area

【横断技術領域 / Cross-Technology Area】（主 / Main）計測・分析/Advanced Characterization（副 / Sub）-

【重要技術領域 / Important Technology Area】（主 / Main）革新的なエネルギー変換を可能とするマテリアル/Materials enabling innovative energy conversion（副 / Sub）-

キーワード / Keywords

Advanced Catalysis,放射光/ Synchrotron radiation,エネルギー貯蔵/ Energy storage,メスバウアー分光/ Mossbauer spectroscopy

利用者と利用形態 / User and Support Type

利用者名（課題申請者）/ User Name (Project Applicant)

Triana Carlos

所属名 / Affiliation

Department of Chemistry, Faculty of Science, University of Zurich

共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes

Zhao Han

ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes

三井 隆也,藤原 孝将

利用形態 / Support Type

（主 / Main）共同研究/Joint Research（副 / Sub）-

利用した主な設備 / Equipment Used in This Project

QS-111：放射光メスバウアー分光装置

報告書データ / Report

概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)

Solar-to-fuel conversion based on light-driven water splitting is one of the most promising approaches for future energy security and climate changes. In this blueprint, water oxidation (2H₂O → O₂ + 4H⁺ + 4e^-) is still an unsolved challenge. NiFe-based heterogeneous or homogeneous catalysts show impressive catalytic ability towards water oxidation. But its mechanism is still under debate and needs various techniques for validation. In this current project, we designated coordination-driven NiFe dual atom catalysts. However, the electronic and structural environment of the catalysts is still ambiguous. Synchrotron radiation ⁵⁷Fe Mössbauer spectroscopy (SRMS) being highly sensitive to the ⁵⁷Fe nuclei and related ligand vibrations, this proposed experiment offers an excellent opportunity to directly detect the possible high valent catalytic Fe-Oxo species in spent catalysts after catalysis and differentiate oxygen binding orientation at Fe site as well as spin/valence state of Fe species over our newly fabricated catalysts. To this end, we aim for cutting-edge SRMS experiments to give solid evidence of Fe atomic configuration and electronic structure in our samples. In addition, we investigated the possibility of operando measurements using our home-made cell.

実験 / Experimental

The experiments were performed at the beamline BL11XU of SPring-8. The ⁵⁷Fe Mössbauer spectra were measured using a nuclear Bragg monochromator and focusing optics. The synchrotron radiation (SR) from the undulator was monochromatized to a bandwidth of 2.5 meV at 14.4 keV by monochromators. The SR was irradiated on a ⁵⁷FeBO₃ single crystal placed downstream of the high-resolution monochromator. For the ex-situ measurements, the sample was pressed into the tablets for measurements. For our operando measurements, the sample was firstly prepared on the carbon paper by drop-casting. Then it was immoblized on our home-made cell which is controlled by the portable potentiostat. All the measurement was performed under ambient temperature and pressure.

結果と考察 / Results and Discussion

Overall the measurement is successful. We obtained some fundantmental data to interpret the electronic structure of our sample. This would help us further elucidate the structure-function relationship. We noticed the composition-induced structure difference from our ex-situ measurements as well as the slight spectra difference in reaction during our operando measurements. We expect to use these findings to combine other techniques (X-ray absorption spectroscopy) to reveal the reaction mechanisms.  

図・表・数式 / Figures, Tables and Equations

Figure1

その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)

We gratefully acknowledge the BL11XU beamline for the allocation of beamtime and Dr. Fujiware Kosuke and Dr. Mitsui Takaya for their assistance in helping with the measurements.

成果発表・成果利用 / Publication and Patents

論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)

口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.

特許 / Patents

特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件