{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T13:00:15Z","timestamp":1789909215190,"version":"4.0.1"},"reference-count":32,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T00:00:00Z","timestamp":1765411200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008227","name":"University of South Africa","doi-asserted-by":"crossref","award":["150341"],"award-info":[{"award-number":["150341"]}],"id":[{"id":"10.13039\/501100008227","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Membrane electrolytes play a critical role in energy conversion devices. The development of stable, efficient membrane electrolytes is urgent and demands paramount attention for the successful commercialization of fuel cells. Chitosan, a naturally occurring material, and silica particles were used as precursors for organic\u2013inorganic membrane polymers. The silica nanoparticles were prepared by the sol\u2013gel and Stober methods and characterized using various techniques, including XRD, FTIR, etc. The silica-incorporated membranes show improved properties, with the sulfur-functionalized membranes having optimal proton conductivity, ion-exchange capacity, and tensile strength of 0.0238 S\/cm, 2.86 meq\/g, and 7.3 MPa, respectively. It also showed the lowest methanol permeability. This was clear proof that membrane functionalization has a positive impact on tuning the properties of electrolyte membranes and should be further explored in membrane development.<\/jats:p>","DOI":"10.3390\/polym17243281","type":"journal-article","created":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T11:17:27Z","timestamp":1765451847000},"page":"3281","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Nano-Silica-Modified Chitosan-Based Membranes for Application in Direct Methanol Fuel Cells"],"prefix":"10.3390","volume":"17","author":[{"given":"Livhuwani Elsie","family":"Modau","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering, University of South Africa, Florida 1710, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tebogo","family":"Mashola","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of South Africa, Florida 1710, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3789-0874","authenticated-orcid":false,"given":"Rudzani Annetjie","family":"Sigwadi","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of South Africa, Florida 1710, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1109-9515","authenticated-orcid":false,"given":"Touhami","family":"Mokrani","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of South Africa, Florida 1710, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6250-5157","authenticated-orcid":false,"given":"Fulufhelo","family":"Nemavhola","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering and the Built Environment, Durban University of Technology, Durban 4000, South Africa"},{"name":"College of Graduate Studies, University of South Africa, Pretoria 0001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rosli, N.A.H., Loh, K.S., Wong, W.Y., Yunus, R.M., Lee, T.K., Ahmad, A., and Chong, S.T. 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