Publisher: Royal Society of Chemistry (RSC)

Issue: 17

License: [{"start"=>{"date-parts"=>[[2025, 7, 14]], "date-time"=>"2025-07-14T00:00:00Z", "timestamp"=>1752451200000}, "content-version"=>"vor", "delay-in-days"=>194, "URL"=>"http://creativecommons.org/licenses/by/3.0/"}]

Publication date(s): 2025/09/07 (print) 2025/07/14 (online)

Pages: 5046-5054

Volume: 15 Issue: {"issue"=>"17", "published-print"=>{"date-parts"=>[[2025, 8, 26]]}}

Journal: Catalysis Science & Technology

Link: [{"URL"=>"http://pubs.rsc.org/en/content/articlepdf/2025/CY/D5CY00336A", "content-type"=>"unspecified", "content-version"=>"vor", "intended-application"=>"similarity-checking"}]

While carbon-supported iron nanostructures are able to provide inexpensive frameworks where the dispersion of single-atom centres enables unique catalytic properties for carbon dioxide functionalization, detailed understanding of the structure of the transition metals is often prevented by the heterogeneous nature of the hosting C matrix and the variety of available sites, consequently hindering the understanding and development of CO2 reduction chemistry. Herein, we report an experimental and computational spectroscopic investigation of few-layer graphene-based samples decorated with Fe atoms immobilised at the edges and in-plane defects of the graphene layers. We find that Fe–OH bound to N-terminated edge sites or in-plane defects of the graphene layers reacts with CO2, forming bicarbonates. A similar reactivity is observed for Fe–OH bound to C-terminated edge sites, whereas Fe–OH coordinated to C-terminated in-plane defects remains unreactive towards CO2. In stark contrast, FeN4 sites in Fe–porphyrin present a direct, carbon-atom-mediated interaction with CO2. These results provide insights into the local coordination environment of iron and its role in the reactivity towards CO2 activation.