{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,17]],"date-time":"2026-05-17T05:06:21Z","timestamp":1778994381139,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T00:00:00Z","timestamp":1778716800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Reduced graphene oxide (rGO) wrapped with poly(styrenesulfonate) (PSS) forms a stable hybrid material (rGO\/PSS) capable of producing ultrathin films with promising barrier properties for Direct Methanol Fuel Cell (DMFC) applications. These films aim to mitigate methanol crossover, one of the major limitations of DMFC technology. In this work, we investigate the mechanisms underlying the methanol barrier effect of rGO\/PSS, while maintaining water permeability. Classical Molecular Dynamics simulations were employed to explore the structural and dynamic properties of rGO\/PSS at different polymer ionization fractions in a solvent mixture of water, methanol, and hydronium. The influence of the sulfonation fraction on film self-assembly was analyzed, including its impact on PSS conformation, rGO sheet distribution, and PSS\u2013rGO interactions. Finally, the effect of the rGO\/PSS structure on solvent diffusion was investigated, and the mechanisms responsible for the selective transport of methanol were elucidated.<\/jats:p>","DOI":"10.3390\/molecules31101657","type":"journal-article","created":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T13:04:09Z","timestamp":1778763849000},"page":"1657","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Computational Insights into Selective Water\u2013Methanol Transport in rGO\/PSS Composite Films"],"prefix":"10.3390","volume":"31","author":[{"given":"Jo\u00e3o Felipe da Silva","family":"Almeida","sequence":"first","affiliation":[{"name":"Instituto de F\u00edsica, Universidade Federal de Uberl\u00e2ndia, Uberl\u00e2ndia 38408-100, MG, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nathan Rabelo","family":"Martins","sequence":"additional","affiliation":[{"name":"Instituto de Ci\u00eancias Exatas e Tecnol\u00f3gicas, Universidade Federal de Vi\u00e7osa, Campus Rio Parana\u00edba, Rio Parana\u00edba 38810-000, MG, Brazil"},{"name":"Department of Physics, Texas State University, San Marcos, TX 78666, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6572-5406","authenticated-orcid":false,"given":"Daiane Damasceno","family":"Borges","sequence":"additional","affiliation":[{"name":"Instituto de F\u00edsica, Universidade Federal de Uberl\u00e2ndia, Uberl\u00e2ndia 38408-100, MG, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5464","DOI":"10.1021\/acs.chemrev.5b00620","article-title":"Noncovalent Functionalization of Graphene and Graphene Oxide for Energy Materials, Biosensing, Catalytic, and Biomedical Applications","volume":"116","author":"Georgakilas","year":"2016","journal-title":"Chem. 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