{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T14:41:10Z","timestamp":1778337670882,"version":"3.51.4"},"reference-count":46,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2023,7,13]],"date-time":"2023-07-13T00:00:00Z","timestamp":1689206400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Foundation for Science and Technology (FCT, Portugal)","doi-asserted-by":"publisher","award":["UIDP\/04540\/2020"],"award-info":[{"award-number":["UIDP\/04540\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>Green hydrogen production seems to be the best route to achieve a sustainable alternative to fossil fuels, as hydrogen has the highest energy density on a mass basis and its combustion does not produce greenhouse gases. Water electrolysis is the method of choice for producing green hydrogen. Among commercially available water electrolysis systems, alkaline water electrolysis (AWE) is the most well-established technology, which, nevertheless, still needs to improve its efficiency. Since the electrodes\u2019 performance is of utmost importance for electrolysis efficiency, nickel foam (NF) and stainless steel foam (SSF) electrodes were analyzed via voltammetry to validate their catalytic activity toward the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in 30 wt.% NaOH electrolyte solution. Moreover, at a current density of 50 mA cm\u22122, the NF and the SSF exhibited good stability, with the potential for HER and OER stabilizing at \u22120.5 V and 1.6 V vs. reversible hydrogen electrode. A lab-scale electrolyzer attained current densities of 10, 20, and 50 mA cm\u22122 at small cell voltages of 1.70 V, 1.80 V, and 1.95 V. The results validated NF and SSF as electrodes for a high-performance AWE electrolyzer, especially at higher temperatures. They ensured the progress for the project\u2019s next stage, i.e., constructing an electrolyzer at a pilot scale.<\/jats:p>","DOI":"10.3390\/su151411011","type":"journal-article","created":{"date-parts":[[2023,7,14]],"date-time":"2023-07-14T00:28:06Z","timestamp":1689294486000},"page":"11011","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Insights on the Performance of Nickel Foam and Stainless Steel Foam Electrodes for Alkaline Water Electrolysis"],"prefix":"10.3390","volume":"15","author":[{"given":"Ana L.","family":"Santos","sequence":"first","affiliation":[{"name":"TecnoVeritas\u2014Servi\u00e7os de Engenharia e Sistemas Tecnol\u00f3gicos, Lda, 2640-486 Mafra, Portugal"},{"name":"Center of Physics and Engineering of Advanced Materials, Laboratory for Physics of Materials and Emerging Technologies, Chemical Engineering Department, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3357-3871","authenticated-orcid":false,"given":"Maria Jo\u00e3o","family":"Cebola","sequence":"additional","affiliation":[{"name":"CBIOS\u2014Center for Research in Biosciences & Health Technologies, Universidade Lus\u00f3fona de Humanidades e Tecnologias, Campo Grande 376, 1749-024 Lisbon, Portugal"},{"name":"CERENA\u2014Centre for Natural Resources and the Environment, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"},{"name":"CiiEM\u2014Centro de Investiga\u00e7\u00e3o Interdisciplinar Egas Moniz, Campus Universit\u00e1rio, Quinta da Granja, 2829-511 Caparica, Portugal"}]},{"given":"Jorge","family":"Antunes","sequence":"additional","affiliation":[{"name":"TecnoVeritas\u2014Servi\u00e7os de Engenharia e Sistemas Tecnol\u00f3gicos, Lda, 2640-486 Mafra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7920-2638","authenticated-orcid":false,"given":"Diogo M. F.","family":"Santos","sequence":"additional","affiliation":[{"name":"Center of Physics and Engineering of Advanced Materials, Laboratory for Physics of Materials and Emerging Technologies, Chemical Engineering Department, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"392","DOI":"10.1016\/j.est.2019.03.001","article-title":"Advances in alkaline water electrolyzers: A review","volume":"23","author":"David","year":"2019","journal-title":"J. Energy Storage"},{"key":"ref_2","unstructured":"(2021, May 27). Communication COM\/2020\/301: A Hydrogen Strategy for a Climate-Neutral Europe. 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