{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T21:53:56Z","timestamp":1774475636949,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2022,8,25]],"date-time":"2022-08-25T00:00:00Z","timestamp":1661385600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"French PIA project \u201cLorraine Universit\u00e9 d\u2032Excellence\u201d"},{"name":"CPER (program SusChemProc)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Iron (II) tris(2,2\u2032-bipyridine) complexes, [Fe(bpy)3]2+, have been synthesized and immobilized in organosulfonate-functionalized nanostructured silica thin films taking advantage of the stabilization of [Fe(H2O)6]2+ species by hydrogen bonds to the anionic sulfonate moieties grafted to the silica nanopores. In a first step, thiol-based silica films have been electrochemically generated on indium tin oxide (ITO) substrates by co-condensation of 3-mercaptopropyltrimethoxysilane (MPTMS) and tetraethoxysilane (TEOS). Secondly, the thiol function has been modified to sulfonate by chemical oxidation using hydrogen peroxide in acidic medium as an oxidizing agent. The immobilization of [Fe(bpy)3]2+ complexes has been performed in situ in two consecutive steps: (i) impregnation of the sulfonate functionalized silica films in an aqueous solution of iron (II) sulfate heptahydrate; (ii) dipping of the iron-containing mesostructures in a solution of bipyridine ligands in acetonitrile. The in situ formation of the [Fe(bpy)3]2+ complex is evidenced by its characteristic optical absorption spectrum, and elemental composition analysis using X-ray photoelectron spectroscopy. The measured optical and electrochemical properties of immobilized [Fe(bpy)3]2+ complexes are not altered by confinement in the nanostructured silica thin film.<\/jats:p>","DOI":"10.3390\/molecules27175444","type":"journal-article","created":{"date-parts":[[2022,8,26]],"date-time":"2022-08-26T02:04:32Z","timestamp":1661479472000},"page":"5444","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Weak Coordinating Character of Organosulfonates in Oriented Silica Films: An Efficient Approach for Immobilizing Cationic Metal-Transition Complexes"],"prefix":"10.3390","volume":"27","author":[{"given":"Samuel","family":"Ahoulou","sequence":"first","affiliation":[{"name":"LCPME, CNRS, Universite de Lorraine, F-54000 Nancy, France"},{"name":"CRM2, CNRS, Universite de Lorraine, F-54000 Nancy, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Clara","family":"Richart","sequence":"additional","affiliation":[{"name":"LCPME, CNRS, Universite de Lorraine, F-54000 Nancy, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"C\u00e9dric","family":"Carteret","sequence":"additional","affiliation":[{"name":"LCPME, CNRS, Universite de Lorraine, F-54000 Nancy, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"S\u00e9bastien","family":"Pillet","sequence":"additional","affiliation":[{"name":"CRM2, CNRS, Universite de Lorraine, F-54000 Nancy, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Neus","family":"Vil\u00e0","sequence":"additional","affiliation":[{"name":"LCPME, CNRS, Universite de Lorraine, F-54000 Nancy, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3633-200X","authenticated-orcid":false,"given":"Alain","family":"Walcarius","sequence":"additional","affiliation":[{"name":"LCPME, CNRS, Universite de Lorraine, F-54000 Nancy, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"969","DOI":"10.1080\/0095897022000002295","article-title":"Mono-Sulfonated Derivatives of Triphenylphosphine, [NH4]TPPMS and M(TPPMS)2 (TPPMS = P(Ph)2(m-C6H4SO3\u2212); M = Mn2+, Fe2+, Co2+ and Ni2+). 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