Site-specific axial oxygen coordinated FeN4 active sites for highly selective electroreduction of carbon dioxide
Regulating the coordination environment via heteroatoms to break the symmetrical electronic structure of M-N active sites provides a promising route to engineer metal-nitrogen-carbon catalysts for electrochemical CO reduction reaction. However, it remains challenging to realize a site-specific intro...
| Autores: | , , , , , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2022 |
| País: | España |
| Institución: | Universitat Autònoma de Barcelona |
| Repositorio: | Dipòsit Digital de Documents de la UAB |
| Idioma: | inglés |
| OAI Identifier: | oai:ddd.uab.cat:266329 |
| Acceso en línea: | https://ddd.uab.cat/record/266329 https://dx.doi.org/urn:doi:10.1002/adfm.202111446 |
| Access Level: | acceso abierto |
| Palabra clave: | CO generation CO2 electroreduction FeN4-O active sites Metal-organic frameworks Single atom catalysts |
| Sumario: | Regulating the coordination environment via heteroatoms to break the symmetrical electronic structure of M-N active sites provides a promising route to engineer metal-nitrogen-carbon catalysts for electrochemical CO reduction reaction. However, it remains challenging to realize a site-specific introduction of heteroatoms at atomic level due to their energetically unstable nature. Here, this paper reports a facile route via using an oxygen- and nitrogen-rich metal-organic framework (MOF) (IRMOF-3) as the precursor to construct the Fe-O and Fe-N chelation, simultaneously, resulting in an atomically dispersed axial O-coordinated FeN active site. Compared to the FeN active sites without O coordination, the formed FeN-O sites exhibit much better catalytic performance toward CO, reaching a maximum FE of 95% at -0.50 V versus reversible hydrogen electrode. To the best of the authors' knowledge, such performance exceeds that of the existing Fe-N-C-based catalysts derived from sole N-rich MOFs. Density functional theory calculations indicate that the axial O-coordination regulates the binding energy of intermediates in the reaction pathways, resulting in a smoother desorption of CO and increased energy for the competitive hydrogen production. |
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