CO Cryo‐Sorption as a Surface‐Sensitive Spectroscopic Probe of the Active Site Density of Single‐Atom Catalysts
Abstract Quantifying the number of active sites is a crucial aspect in the performance evaluation of single metal‐atom electrocatalysts. A possible realization is using adsorbing gas molecules that selectively bind to the single‐atom transition metal and then probing their surface density using spectroscopic tools. Herein, using in situ X‐ray photoelectron spectroscopy (XPS) and near edge X‐ray absorption fine structure (NEXAFS) spectroscopy, we detect adsorbed CO gas molecules on a FeNC oxygen reduction single atom catalyst. Correlating XPS and NEXAFS, we develop a simple surface‐ and chemically‐sensitive protocol to accurately and quickly quantify the active site density. Density functional theory‐based X‐ray spectra simulations reaffirm the assignment of the spectroscopic fingerprints of the CO molecules adsorbed at Fe‐N 4 ‐C sites, and provide additional unexpected structural insights about the active site needed to explain the low‐temperature CO adsorption. Our work represents an important step towards an accurate quantitative catalytic performance evaluation, and thus towards developing reliable material design principles and catalysts.
Authors
- Geunsu Bae (ORCID: https://orcid.org/0000-0002-6714-1647)
- Frédéric Jaouen (ORCID: https://orcid.org/0000-0001-9836-3261)
- Reinhard J. Maurer (ORCID: https://orcid.org/0000-0002-3004-785X)
- A. Velmurugan (ORCID: https://orcid.org/0000-0003-3165-9126)
- Hafiz Ghulam Abbas (ORCID: https://orcid.org/0000-0002-1734-1296)
- Byeong Jun (ORCID: https://orcid.org/0000-0002-8703-2309)
- Geonhwa Kim (ORCID: https://orcid.org/0000-0002-6203-7613)
- Stefan Ringe (ORCID: https://orcid.org/0000-0002-7804-1406)
- Benedikt P. Klein (ORCID: https://orcid.org/0000-0002-6205-8879)
- Beomgyun Jeong (ORCID: https://orcid.org/0000-0003-3890-1464)
- Chang Hyuck Choi (ORCID: https://orcid.org/0000-0002-2231-6116)
- Dongwoo Kim (ORCID: https://orcid.org/0000-0002-6515-5260)
- Ki-Jeong Kim (ORCID: https://orcid.org/0000-0001-9233-3096)
- Young Dok Kim
Institutions
- École Nationale Supérieure de Chimie de Montpellier (FR)
- Pohang University of Science and Technology (KR)
- Centre National de la Recherche Scientifique (FR)
- Korea University (KR)
- Université de Montpellier (FR)
- University of Warwick (GB)
- Centre National pour la Recherche Scientifique et Technique (CNRST) (MA)
- Institut Charles Gerhardt Montpellier (FR)
- Advanced Institute of Convergence Technology (KR)
- Korea Basic Science Institute (KR)
- Sungkyunkwan University (KR)
Publication Details
- Journal
- Angewandte Chemie
- Published
- 2025-01-09
- DOI
- https://doi.org/10.1002/ange.202420673
- Primary Topic
- Catalytic Processes in Materials Science
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- UK Research and Innovation
- National Research Foundation
- Pohang University of Science and Technology
- Korea Institute of Science and Technology
- Korea Institute of Science and Technology Information
- Korea Basic Science Institute
- National Research Foundation of Korea
- Ministry of Science and ICT, South Korea
- National Supercomputing Center, Korea Institute of Science and Technology Information