{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T09:27:13Z","timestamp":1774862833363,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,29]],"date-time":"2026-03-29T00:00:00Z","timestamp":1774742400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t              https:\/\/ror.org\/00snfqn58","doi-asserted-by":"publisher","award":["SFRH\/BD\/151392\/2021"],"award-info":[{"award-number":["SFRH\/BD\/151392\/2021"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National funds","award":["UID\/00511\/2025"],"award-info":[{"award-number":["UID\/00511\/2025"]}]},{"name":"National funds","award":["UID\/PRR\/00511\/2025"],"award-info":[{"award-number":["UID\/PRR\/00511\/2025"]}]},{"name":"National funds","award":["LA\/P\/0045\/2020"],"award-info":[{"award-number":["LA\/P\/0045\/2020"]}]},{"name":"National funds","award":["UID\/50006\/2023"],"award-info":[{"award-number":["UID\/50006\/2023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>The PGM-free Fe\u2013Ni\u2013Co trimetallic catalysts developed in this study demonstrated outstanding performance for the oxygen evolution reaction (OER), achieving overpotentials as low as 300 mV at 10 mA cm\u22122 in rotating disk electrode (RDE) measurements, a value competitive with the most efficient non-noble electrocatalysts reported in the literature. This study validates the strong catalytic performance of the baseline trimetallic configuration and provides important insights into the relationships among synthesis, structure, and morphology that govern catalyst activity. In particular, the findings highlight that although organic additives can be promising modifiers, the interaction between precursors and transition metals must be carefully controlled to avoid active-site isolation when designing efficient catalysts for sustainable hydrogen production. Actually, to further enhance catalytic activity, the nitrogen-rich precursor melamine was introduced into the supported trimetallic catalyst and then carbonized. However, no improvement in OER performance was observed. During carbonization, melamine promotes the formation of tip-growth carbon nanotubes, which mechanically disrupt the catalyst structure and degrade the supported active phase.<\/jats:p>","DOI":"10.3390\/app16073310","type":"journal-article","created":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T08:22:36Z","timestamp":1774858956000},"page":"3310","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of Melamine on the Oxygen Evolution Reaction Performance of PGM-Free Catalysts Under Alkaline Conditions"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4598-5985","authenticated-orcid":false,"given":"Jorge","family":"Teixeira","sequence":"first","affiliation":[{"name":"LEPABE, Chemical Engineering Department, Faculdade de Engenharia da Universidade do Porto, 4200-465 Porto, Portugal"},{"name":"Bondalti Chemicals, Rua do Amon\u00edaco Portugu\u00eas n<sup>o<\/sup>10, 3860-680 Estarreja, Portugal"},{"name":"LAQV-REQUIMTE, Chemistry Department, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"},{"name":"ALiCE\u2013Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7672-0253","authenticated-orcid":false,"given":"Filipa","family":"Franco","sequence":"additional","affiliation":[{"name":"Bondalti Chemicals, Rua do Amon\u00edaco Portugu\u00eas n<sup>o<\/sup>10, 3860-680 Estarreja, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9446-0897","authenticated-orcid":false,"given":"Svetlozar","family":"Velizarov","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Chemistry Department, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2472-3265","authenticated-orcid":false,"given":"Ad\u00e9lio","family":"Mendes","sequence":"additional","affiliation":[{"name":"LEPABE, Chemical Engineering Department, Faculdade de Engenharia da Universidade do Porto, 4200-465 Porto, Portugal"},{"name":"ALiCE\u2013Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Alia, S.M., and Danilovic, N. 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