{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T13:01:44Z","timestamp":1785416504082,"version":"3.56.0"},"reference-count":36,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T00:00:00Z","timestamp":1776988800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52371210"],"award-info":[{"award-number":["52371210"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52371210"],"award-info":[{"award-number":["52371210"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Guangzhou National Laboratory","award":["No. GZNL2024A01028"],"award-info":[{"award-number":["No. GZNL2024A01028"]}]},{"award":["No. GZNL2024A01028"],"award-info":[{"award-number":["No. GZNL2024A01028"]}],"id":[{"id":"https:\/\/ror.org\/03ybmxt82","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011202","name":"State Key Laboratory of Catalysis","doi-asserted-by":"publisher","award":["E404082900"],"award-info":[{"award-number":["E404082900"]}],"id":[{"id":"10.13039\/501100011202","id-type":"DOI","asserted-by":"publisher"}]},{"award":["E404082900"],"award-info":[{"award-number":["E404082900"]}],"id":[{"id":"https:\/\/ror.org\/04wsvdt21","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>While metal-assisted chemical etching (MACE) or metal-catalyzed electroless etching of silicon in oxidizing HF solutions typically employs noble metals as catalysts, this work investigates oxide-catalyzed chemical etching (OACE) using RuO2 to induce localized silicon etching in aqueous H2O2-HF solutions. RuO2 particles confine the reaction to localized sites. The formation of Ru2O3 during etching suggests that RuO2 injects holes into silicon and is simultaneously reduced to Ru2O3. The oxidized silicon is locally dissolved in aqueous HF solution, and the pores are generated. A cyclic redox mechanism is proposed: RuO2 is reduced to Ru2O3 by extracting electrons from silicon valence band, while Ru2O3 is rapidly reoxidized by H2O2, sustaining the etching process until H2O2 is exhausted. This work challenges the conventional assumption that the catalyst remains unchanged during MACE and offers novel insights into oxide-catalyzed silicon etching mechanisms.<\/jats:p>","DOI":"10.3390\/ma19091734","type":"journal-article","created":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T12:29:11Z","timestamp":1777033751000},"page":"1734","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Mechanism of Ruthenium Oxide Catalyzed Electroless Etching of Silicon in Oxidizing HF Solution"],"prefix":"10.3390","volume":"19","author":[{"given":"Bing","family":"Bai","sequence":"first","affiliation":[{"name":"Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Key Laboratory of Energy Conversion and Storage Materials, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yingqi","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Key Laboratory of Energy Conversion and Storage Materials, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Xu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Key Laboratory of Energy Conversion and Storage Materials, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peiao","family":"Lu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Key Laboratory of Energy Conversion and Storage Materials, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiakun","family":"Luo","sequence":"additional","affiliation":[{"name":"Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Key Laboratory of Energy Conversion and Storage Materials, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinyu","family":"Wu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Key Laboratory of Energy Conversion and Storage Materials, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0442-8103","authenticated-orcid":false,"given":"Kui-Qing","family":"Peng","sequence":"additional","affiliation":[{"name":"Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Key Laboratory of Energy Conversion and Storage Materials, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"165632","DOI":"10.1016\/j.cej.2025.165632","article-title":"Scalable fabrication of ultra-long silicon nanowires via H2O2-enhanced MACE for flexible hydrogen sensors","volume":"520","author":"Shim","year":"2025","journal-title":"Chem. 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