{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T23:28:33Z","timestamp":1772580513152,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T00:00:00Z","timestamp":1770163200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Union","doi-asserted-by":"crossref","award":["NORTE 2030 Regional Program"],"award-info":[{"award-number":["NORTE 2030 Regional Program"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.","award":["UID\/50020\/2025"],"award-info":[{"award-number":["UID\/50020\/2025"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.","award":["LA\/P\/0045\/2020"],"award-info":[{"award-number":["LA\/P\/0045\/2020"]}]},{"name":"FCT","award":["SFRH\/BD\/149838\/2019"],"award-info":[{"award-number":["SFRH\/BD\/149838\/2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["C"],"abstract":"<jats:p>Reducing emissions of nitrogen compounds represents a significant challenge in environmental protection, and catalytic treatment is an effective approach. Carbon-based catalysts offer a promising alternative by exploiting the redox properties of carbon materials and eliminating the need for external reducing agents. In this study, nitrogen-free and nitrogen-doped activated carbons were used for NO reduction. The catalysts were developed by incorporating transition metals (Cu and Fe), alkali metals (K), and bimetallic Cu-K formulations. The addition of K to Cu and the presence of nitrogen functionalities improved the catalytic performance and an optimum Cu\/K ratio was identified. The best-performing catalyst, AC_M_BM@5Cu5K, achieved 100% NO conversion at 410 \u00b0C, producing mainly N2 and CO2, while N2O was detected as an intermediate and CO was not observed. The catalyst\u2019s stability was evaluated in a 100 h continuous test at 376 \u00b0C, during which the catalyst maintained approximately 90% NO conversion for 40 h before deactivation. The deactivation mechanism is discussed in detail.<\/jats:p>","DOI":"10.3390\/c12010014","type":"journal-article","created":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T09:02:01Z","timestamp":1770195721000},"page":"14","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Bimetallic Catalysts on Activated Carbon for Enhanced NO Reduction"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5547-8066","authenticated-orcid":false,"given":"Patr\u00edcia S. F.","family":"Ramalho","sequence":"first","affiliation":[{"name":"LSRE-LCM, ALiCE, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9015-1237","authenticated-orcid":false,"given":"Ol\u00edvia S. G. P.","family":"Soares","sequence":"additional","affiliation":[{"name":"LSRE-LCM, ALiCE, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0395-8199","authenticated-orcid":false,"given":"Jos\u00e9 L.","family":"Figueiredo","sequence":"additional","affiliation":[{"name":"LSRE-LCM, ALiCE, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5447-2471","authenticated-orcid":false,"given":"Manuel F. 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