{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T05:11:54Z","timestamp":1783746714505,"version":"3.55.0"},"reference-count":38,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T00:00:00Z","timestamp":1783555200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Molybdenum-doped xerogel composites were prepared and applied in the electro-degradation of tetracycline (TTC), an antibiotic commonly prescribed for the treatment of bacterial infections. Xerogels containing 1, 6, and 14 wt% Mo were synthesized using an RF sol\u2013gel polymerization method in cylindrical molds and were subsequently characterized in terms of their textural, chemical, and electrochemical properties, focusing on the oxygen reduction reaction (ORR). Textural characterization revealed well-developed surface areas and mesoporosity. Electrochemical analysis showed that Mo loading plays a vital role in the ORR mechanism: lower metal content favors the four-electron pathway with lower hydrogen peroxide selectivity, whereas higher Mo loadings promote bifunctional behavior, enabling both in situ H2O2 generation and hydroxyl radical production. Undoped and doped xerogels were very active for TTC degradation via the electro-Fenton process, but the presence of MoO3 and Mo2C phases improved up to 12% in removal efficiency after 480 min of treatment.<\/jats:p>","DOI":"10.3390\/gels12070617","type":"journal-article","created":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T10:16:22Z","timestamp":1783592182000},"page":"617","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Molybdenum\u2013Carbon Xerogel Composites for ORR-Based Electro-Catalytic Applications"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-6790-9503","authenticated-orcid":false,"given":"Luis A.","family":"Cavazos-Cuello","sequence":"first","affiliation":[{"name":"Materiales Polifuncionales Basados en Carbono (UGR-Carbon), Dpto. Qu\u00edmica Inorg\u00e1nica, Unidad de Excelencia Qu\u00edmica Aplicada a Biomedicina y Medioambiente, Universidad de Granada, ES18071 Granada, Spain"},{"name":"Facultad de Ciencias Qu\u00edmicas, Universidad Aut\u00f3noma de Nuevo Le\u00f3n, Av. Universidad S\/N, Cd. Universitaria, San Nicol\u00e1s de los Garza 66455, N.L., Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9177-8990","authenticated-orcid":false,"given":"Abdelhakim","family":"Elmouwahidi","sequence":"additional","affiliation":[{"name":"Materiales Polifuncionales Basados en Carbono (UGR-Carbon), Dpto. Qu\u00edmica Inorg\u00e1nica, Unidad de Excelencia Qu\u00edmica Aplicada a Biomedicina y Medioambiente, Universidad de Granada, ES18071 Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esther","family":"Bail\u00f3n-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Materiales Polifuncionales Basados en Carbono (UGR-Carbon), Dpto. Qu\u00edmica Inorg\u00e1nica, Unidad de Excelencia Qu\u00edmica Aplicada a Biomedicina y Medioambiente, Universidad de Granada, ES18071 Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2134-0907","authenticated-orcid":false,"given":"Jacob Josafat","family":"Salazar R\u00e1bago","sequence":"additional","affiliation":[{"name":"Facultad de Ciencias Qu\u00edmicas, Universidad Aut\u00f3noma de Nuevo Le\u00f3n, Av. Universidad S\/N, Cd. 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