{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T14:50:21Z","timestamp":1771599021963,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,6,30]],"date-time":"2025-06-30T00:00:00Z","timestamp":1751241600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"MCIN\/AEI\/10.13039\/501100011033\/FEDER-UE","award":["PID2022-139493OA-100"],"award-info":[{"award-number":["PID2022-139493OA-100"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033\/FEDER-UE","award":["RyC2021-031456-I"],"award-info":[{"award-number":["RyC2021-031456-I"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033\/FEDER-UE","award":["CNS2023-144627"],"award-info":[{"award-number":["CNS2023-144627"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033 and European Union NexGenerationEU\/PRTR","award":["PID2022-139493OA-100"],"award-info":[{"award-number":["PID2022-139493OA-100"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033 and European Union NexGenerationEU\/PRTR","award":["RyC2021-031456-I"],"award-info":[{"award-number":["RyC2021-031456-I"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033 and European Union NexGenerationEU\/PRTR","award":["CNS2023-144627"],"award-info":[{"award-number":["CNS2023-144627"]}]},{"name":"Severo Ochoa Program","award":["PID2022-139493OA-100"],"award-info":[{"award-number":["PID2022-139493OA-100"]}]},{"name":"Severo Ochoa Program","award":["RyC2021-031456-I"],"award-info":[{"award-number":["RyC2021-031456-I"]}]},{"name":"Severo Ochoa Program","award":["CNS2023-144627"],"award-info":[{"award-number":["CNS2023-144627"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microwave"],"abstract":"<jats:p>There is currently an effort to scale up sol\u2013gel nanomaterials without compromising quality, and microwave heating can pave the way for this due to its heating efficiency, resulting in a fast and homogeneous process. In this work, the sol\u2013gel synthesis of transition metal aerogels, specifically iron-based aerogels, is studied using a microwave-assisted sol\u2013gel methodology in an open-system multimode device as a potential route to scale-up production. Different approaches were tested to evaluate the best way to increase yield per batch, with different vessel shapes and volumes. It is shown that the shape and size of the vessel can be determinant in the interaction with microwaves and, thus, in the heating process, influencing the sol\u2013gel reactions and the characteristics and homogeneity of the obtained nanomaterials. It has been found that a wide vessel is preferable to a tall and narrow one since the heating process is more homogeneous in the former and the sol\u2013gel and cross-linking reactions take place earlier, which improves the mechanical properties of the final nanomaterial. For mass production of nanomaterials, the interaction of the reagents with the microwave field must be considered, and this depends not only on their nature but also on their volume, shape, and arrangement inside the cavity.<\/jats:p>","DOI":"10.3390\/microwave1020006","type":"journal-article","created":{"date-parts":[[2025,7,1]],"date-time":"2025-07-01T05:28:28Z","timestamp":1751347708000},"page":"6","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Overcoming Scaling Challenges in Sol\u2013Gel Synthesis: A Microwave-Assisted Approach for Iron-Based Energy Materials"],"prefix":"10.3390","volume":"1","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7408-8031","authenticated-orcid":false,"given":"Judith","family":"Gonz\u00e1lez-Lav\u00edn","sequence":"first","affiliation":[{"name":"Instituto de Ciencia y Tecnolog\u00eda del Carbono, INCAR-CSIC, 33011 Oviedo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5388-1169","authenticated-orcid":false,"given":"Ana","family":"Arenillas","sequence":"additional","affiliation":[{"name":"Instituto de Ciencia y Tecnolog\u00eda del Carbono, INCAR-CSIC, 33011 Oviedo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5003-0035","authenticated-orcid":false,"given":"Natalia","family":"Rey-Raap","sequence":"additional","affiliation":[{"name":"Instituto de Ciencia y Tecnolog\u00eda del Carbono, INCAR-CSIC, 33011 Oviedo, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,30]]},"reference":[{"key":"ref_1","unstructured":"Kozhukharov, S.V. 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