{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T13:40:43Z","timestamp":1762868443177,"version":"build-2065373602"},"reference-count":81,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,2,12]],"date-time":"2021-02-12T00:00:00Z","timestamp":1613088000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Herein, it has been shown that betulin can be transformed into its biologically active oxo-derivatives (betulone, betulinic and betulonic aldehydes) by liquid-phase oxidation over supported silver catalysts under mild conditions. In order to identify the main factors determining the catalytic behavior of nanosilver catalysts in betulin oxidation, silver was deposited on various alumina supports (\u03b3-alumina and boehmite) using deposition\u2013precipitation with NaOH and incipient wetness impregnation methods, followed by treatment in H2 or O2. Silver catalysts and the corresponding supports were characterized by X-ray diffraction, nitrogen physisorption, inductively coupled plasma optical emission spectroscopy, photoelectron spectroscopy and transmission electron microscopy. It was found that the support nature, preparation and treatment methods predetermine not only the average Ag nanoparticles size and their distribution, but also the selectivity of betulin oxidation, and thereby, the catalytic behavior of Ag catalysts. In fact, the support nature had the most considerable effect. Betulin conversion, depending on the support, increased in the following order: Ag\/boehmite &lt; Ag\/boehmite (calcined) &lt; Ag\/\u03b3-alumina. However, in the same order, the share of side reactions catalyzed by strong Lewis acid centers of the support also increased. Poisoning of the latter by NaOH during catalysts preparation can reduce side reactions. Additionally, it was revealed that the betulin oxidation catalyzed by nanosilver catalysts is a structure-sensitive reaction.<\/jats:p>","DOI":"10.3390\/nano11020469","type":"journal-article","created":{"date-parts":[[2021,2,12]],"date-time":"2021-02-12T18:45:00Z","timestamp":1613155500000},"page":"469","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Supported Silver Nanoparticles as Catalysts for Liquid-Phase Betulin Oxidation"],"prefix":"10.3390","volume":"11","author":[{"given":"Anna","family":"Grigoreva","sequence":"first","affiliation":[{"name":"Research School of Chemistry &amp; Applied Biomedical Sciences, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5150-6787","authenticated-orcid":false,"given":"Ekaterina","family":"Kolobova","sequence":"additional","affiliation":[{"name":"Research School of Chemistry &amp; Applied Biomedical Sciences, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2842-2542","authenticated-orcid":false,"given":"Ekaterina","family":"Pakrieva","sequence":"additional","affiliation":[{"name":"Research School of Chemistry &amp; Applied Biomedical Sciences, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7055-9358","authenticated-orcid":false,"given":"P\u00e4ivi","family":"M\u00e4ki-Arvela","sequence":"additional","affiliation":[{"name":"Johan Gadolin Process Chemistry Centre, \u00c5bo Akademi University, 20500 Turku\/\u00c5bo, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9913-4671","authenticated-orcid":false,"given":"S\u00f3nia A. C.","family":"Carabineiro","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal"},{"name":"LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal"}]},{"given":"Alina","family":"Gorbunova","sequence":"additional","affiliation":[{"name":"Research School of Chemistry &amp; Applied Biomedical Sciences, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0929-3535","authenticated-orcid":false,"given":"Nina","family":"Bogdanchikova","sequence":"additional","affiliation":[{"name":"Centro de Nanociencias y Nanotecnolog\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Ensenada 22800, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0788-2643","authenticated-orcid":false,"given":"Dmitry Yu.","family":"Murzin","sequence":"additional","affiliation":[{"name":"Johan Gadolin Process Chemistry Centre, \u00c5bo Akademi University, 20500 Turku\/\u00c5bo, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9034-4733","authenticated-orcid":false,"given":"Alexey","family":"Pestryakov","sequence":"additional","affiliation":[{"name":"Research School of Chemistry &amp; Applied Biomedical Sciences, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,12]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"Betulin and its derivatives. 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