Single cobalt atoms with unconventional dynamic coordination mechanism for selective ammonia sensor
Developing gas sensors that can simultaneously achieve high sensitivity and selectivity for the detection of a single-type gas remains a significant challenge. Herein we demonstrate cobalt (Co) single atoms with an unconventional dynamically changing coordination structure that could be used as NH<sub>3</sub>-sensing material with superior sensitivity and selectivity. According to the steric effect of 2-methylimidazole (2MI) molecules and carbonyl groups on graphene, the Co single atom is evolved into a bidentate coordinated structure (Co-2MI-G). <i>In-situ</i> characterization and theoretical simulation reveal that the sensing mechanism of Co-2MI-G is the specific chemical adsorption between unsaturated coordinated Co single atoms and NH<sub>3</sub> molecules, causing a reversible switching of coordination number from 2 to 4, a valence state transfer from Co<sup>2+</sup> to Co<sup>3+</sup> of Co single atoms, and a band-gap width from 0.14 eV to 0.50 eV. Consequently, the Co-2MI-G-based gas sensor presents a sensing response of 67.598% for 1 ppm NH<sub>3</sub> and a limit of detection of 2.67 ppb, at least 1.8 times higher than that of state-of-the-art NH<sub>3</sub> sensors, together with robust stability and reproducibility. This work provides an innovative perspective on utilizing single atoms for ultra-selective gas sensing by coordination regulation.
Authors
- Yaguang Li (ORCID: https://orcid.org/0000-0001-9218-0990)
- Qiang Fu (ORCID: https://orcid.org/0000-0001-5316-6758)
- Zhenming Wang (ORCID: https://orcid.org/0000-0002-9706-4427)
- Jianmin Lü (ORCID: https://orcid.org/0000-0003-3280-6466)
- Xinhe Bao (ORCID: https://orcid.org/0000-0001-9404-6429)
- Liang Feng (ORCID: https://orcid.org/0000-0002-7586-8424)
- Zhong‐Shuai Wu (ORCID: https://orcid.org/0000-0003-1851-4803)
- Junyu Chang (ORCID: https://orcid.org/0009-0003-4396-3069)
- Chao Wang (ORCID: https://orcid.org/0000-0002-3234-6917)
- Bing Yang (ORCID: https://orcid.org/0000-0003-3515-0642)
- Yuejiao Li (ORCID: https://orcid.org/0000-0001-7572-5792)
- Yushu Shi (ORCID: https://orcid.org/0000-0002-7445-9952)
- Jianmei Gao (ORCID: https://orcid.org/0000-0001-5544-7748)
- Yifan Yang (ORCID: https://orcid.org/0000-0002-9867-143X)
Institutions
- Qingdao University (CN)
- Qingdao Agricultural University (CN)
- Shandong University (CN)
- Dalian Institute of Chemical Physics (CN)
- Chinese Academy of Sciences (CN)
- Dalian National Laboratory for Clean Energy (CN)
- Marine Biomedical Research Institute of Qingdao (CN)
- Carbon Engineering (Canada) (CA)
- University of Chinese Academy of Sciences (CN)
- Hebei University (CN)
- Beijing City University (CN)
Publication Details
- Journal
- National Science Review
- Published
- 2025-02-04
- DOI
- https://doi.org/10.1093/nsr/nwaf031
- Citations
- 7
- Primary Topic
- Gas Sensing Nanomaterials and Sensors
- Type
- article
- Field-Weighted Citation Impact
- 5.11
Funders
- Salt Science Research Foundation
- National Natural Science Foundation of China
- Chinese Academy of Sciences
- Natural Science Foundation of Hebei Province
- Hebei University
- State Key Laboratory of Catalysis
- Dalian Institute of Chemical Physics
- National Key Research and Development Program of China