{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T11:15:05Z","timestamp":1785496505256,"version":"3.56.0"},"reference-count":59,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2021,11,26]],"date-time":"2021-11-26T00:00:00Z","timestamp":1637884800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006595","name":"Unitatea Executiva Pentru Finantarea Invatamantului Superior a Cercetarii Dezvoltarii si Inovarii","doi-asserted-by":"publisher","award":["TE205\/2021"],"award-info":[{"award-number":["TE205\/2021"]}],"id":[{"id":"10.13039\/501100006595","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006595","name":"Unitatea Executiva Pentru Finantarea Invatamantului Superior a Cercetarii Dezvoltarii si Inovarii","doi-asserted-by":"publisher","award":["PD106\/2020"],"award-info":[{"award-number":["PD106\/2020"]}],"id":[{"id":"10.13039\/501100006595","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Organic resorcinol\u2013formaldehyde (RF) hydrogels were introduced into a hybrid cation-exchange membrane in order to enhance its following properties: water uptake, thermal stability, and ionic conductivity. This study was aimed to investigate the modifications induced by the RF organic clusters that form a uniform distributed network within the perflourosulfonated acid (PFSA) matrix. RF concentration was controlled by resorcinol and formaldehyde impregnation time using water or ethanol solvents. The specific morphological and structural properties were characterized by atomic force microscopy, UV\u2013Vis, and Fourier transform infrared spectroscopy. Thermo-gravimetric analysis was employed to study the thermal stability and degradation processes of the composite membranes. Proton conductivity, as a function of relative humidity (RH) at 80 \u00b0C, was measured using in-plane four-point characterization technique. Compared to the pristine membrane, the PFSA\u2013RF hybrid membranes showed improved thermal stability at up to 46 \u00b0C and higher ionic conductivity for low RF content, especially at low relative humidity, when using ethanol-based solvents. Single fuel cell testing on RF-based membrane\u2013electrode assembly revealed impeccable fuel crossover and power performance at 80 \u00b0C and 40% relative humidity, delivering a 76% increase in power density compared to a reference assembled with a pristine membrane and the same catalyst loadings.<\/jats:p>","DOI":"10.3390\/polym13234123","type":"journal-article","created":{"date-parts":[[2021,12,1]],"date-time":"2021-12-01T02:34:05Z","timestamp":1638326045000},"page":"4123","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Hybrid Proton-Exchange Membrane Based on Perfluorosulfonated Polymers and Resorcinol\u2013Formaldehyde Hydrogel"],"prefix":"10.3390","volume":"13","author":[{"given":"Alexandra Maria Isabel","family":"Trefilov","sequence":"first","affiliation":[{"name":"National R&D Institute for Laser, Plasma and Radiation Physics (INFLPR), 077125 Bucharest-M\u0103gurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriana","family":"Balan","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Bucharest, 3NanoSAE Research Center, 077125 Bucharest-M\u0103gurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ioan","family":"Stamatin","sequence":"additional","affiliation":[{"name":"Faculty of Physics, University of Bucharest, 3NanoSAE Research Center, 077125 Bucharest-M\u0103gurele, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1016\/j.electacta.2019.03.056","article-title":"Hybrid inorganic-organic proton-conducting membranes based on SPEEK doped with WO3 nanoparticles for application in vanadium redox flow batteries","volume":"309","author":"Sun","year":"2019","journal-title":"Electrochim. 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