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Mutable Lewis and Bronsted Acidity of Aluminated SBA-15 as Revealed by NMR of Adsorbed Pyridine-(15)N
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SYSNO ASEP 0365144 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Mutable Lewis and Bronsted Acidity of Aluminated SBA-15 as Revealed by NMR of Adsorbed Pyridine-(15)N Tvůrce(i) Gurinov, A. A. (RU)
Rozhkova, Yu. A. (RU)
Zukal, Arnošt (UFCH-W) RID
Čejka, Jiří (UFCH-W) RID, ORCID, SAI
Shenderovich, I, G. (RU)Zdroj.dok. Langmuir. - : American Chemical Society - ISSN 0743-7463
Roč. 27, č. 19 (2011), s. 12115-12123Poč.str. 9 s. Jazyk dok. eng - angličtina Země vyd. US - Spojené státy americké Klíč. slova 15N NMR ; post-synthesis alumination ; phase Beckmann rearrangement Vědní obor RIV CF - Fyzikální chemie a teoretická chemie CEP KAN100400701 GA AV ČR - Akademie věd GA203/08/0604 GA ČR - Grantová agentura ČR CEZ AV0Z40400503 - UFCH-W (2005-2011) UT WOS 000295187300050 DOI 10.1021/la2017566 Anotace 1H and variable-temperature (15)N NMR techniques have been used to study the effect of the gradual alumination of SBA-15 on the structure and adsorption properties of this mesoporous material. The interpretation of experimental spectra suggests that aluminum chlorhydrol most effectively reacts with silica surfaces in the confinement of the cavities of rough mesopore walls, instead of forming a homogeneous aluminum film. This first leads to a gradual filling of the cavities and finally results in aluminum islands on the inner surfaces of mesopores. In the sample with a Si/Al atomic ratio of 4.1, up to half of the inner surface area of the mesopores is covered with aluminum. The alumination produces Bronsted acid sites attributed to silanol groups interacting with aluminum but does not affect the proton-donating ability of isolated silanol groups. At high Si/Al ratios, the surface contains only one type of Lewis site attributed to tetracoordinated aluminum. Pracoviště Ústav fyzikální chemie J.Heyrovského Kontakt Michaela Knapová, michaela.knapova@jh-inst.cas.cz, Tel.: 266 053 196 Rok sběru 2012
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