{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:59:03Z","timestamp":1787029143644,"version":"build-2736575974"},"reference-count":20,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T00:00:00Z","timestamp":1771372800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Nickel is widely deployed in caustic service, yet its native Ni(OH)2\/NiOOH passive film raises concerns for long service life. Graphene has emerged as a promising corrosion barrier; however, its long-term durability in strongly alkaline media remains largely unexplored. The extended exposure period in a highly caustic solution is a novel aspect of the present work, distinguishing it from previous studies that predominantly examined short-term exposures or focused on neutral and acidic environments. Here, we present the systematic assessment of low-pressure CVD-grown multilayer graphene (MLG) coatings on Ni in highly caustic (0.5 M NaOH) for up to 80 days. Two architectures, a conformal, robust MLG coating (Gr_Ni) and a less robust film (Gr_Ni_DF), were benchmarked against bare Ni. PDP and EIS reveal that Gr_Ni initially delivers nearly 2 orders of magnitude enhancement, as evidenced by the low frequency impedance, accompanied by a broad, high-fidelity capacitive plateau; the impedance still maintains 1.3\u20131.5 orders of magnitude superior after prolonged exposure. In contrast, Gr_Ni_DF undergoes progressive degradation, affording a modest 2-fold benefit over time, consistent with defect-mediated electrolyte ingress. SEM morphologies further corroborate these trends, confirming the superior structural stability of Gr_Ni under extended alkaline immersion.<\/jats:p>","DOI":"10.3390\/nano16040265","type":"journal-article","created":{"date-parts":[[2026,2,18]],"date-time":"2026-02-18T07:50:30Z","timestamp":1771401030000},"page":"265","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Graphene Coatings for Durable and Robust Resistance to Caustic Corrosion of Nickel"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0256-9917","authenticated-orcid":false,"given":"Tanuj","family":"Joshi","sequence":"first","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, Monash University, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3157-634X","authenticated-orcid":false,"given":"R. K.","family":"Singh Raman","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, Monash University, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yiannis","family":"Ventikos","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, Monash University, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9307-0953","authenticated-orcid":false,"given":"Saad","family":"Al-Saadi","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biological Engineering, Monash University, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anthony De","family":"Girolamo","sequence":"additional","affiliation":[{"name":"Department of Chemical and Biological Engineering, Monash University, Clayton 3800, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"296","DOI":"10.1007\/s40195-017-0553-z","article-title":"Localized Corrosion Characteristics of Nickel Alloys: A Review","volume":"30","author":"Klapper","year":"2017","journal-title":"Acta Metall. 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