Deutsch
 
Hilfe Datenschutzhinweis Impressum
  DetailsucheBrowse

Datensatz

DATENSATZ AKTIONENEXPORT
  SiC/MCM-48 and SiC/SBA-15 Nanocomposite Materials

Krawiec, P., Weidenthaler, C., & Kaskel, S. (2004). SiC/MCM-48 and SiC/SBA-15 Nanocomposite Materials. Chemistry of Materials, 16(15), 2869-2880. doi:10.1021/cm034737.

Item is

Basisdaten

einblenden: ausblenden:
Genre: Zeitschriftenartikel

Externe Referenzen

einblenden:

Urheber

einblenden:
ausblenden:
 Urheber:
Krawiec, Piotr1, Autor           
Weidenthaler, Claudia1, Autor           
Kaskel, Stefan2, Autor           
Affiliations:
1Research Department Schüth, Max-Planck-Institut für Kohlenforschung, Max Planck Society, ou_1445589              
2Research Group Kaskel, Max-Planck-Institut für Kohlenforschung, Max Planck Society, ou_1445607              

Inhalt

einblenden:
ausblenden:
Schlagwörter: -
 Zusammenfassung: Silicon carbide (SiC) was infiltrated into the ordered mesoporous molecular sieves MCM-48 and SBA-15 using chemical vapor infiltration (CVI) of dimethyldichlorosilane (DDS) and hydrogen as the carrier gas. The infiltration process was followed ex situ using nitrogen physisorption measurements, small- and wide-angle X-ray diffraction, X-ray photoelectron spectroscopy, IR spectroscopy, and transmission electron microscopy. For MCM-48, infiltration at lower temperatures (1023 K) affords a thin, X-ray amorphous, SiC-based coating on the inner surface of the molecular sieve and the pore size of the mesoporous host decreases from 2.4 nm into the micropore regime (<2 nm). At higher temperature (1163 K), the deposition of 20−30-nm sized β-SiC particles is observed on the outer surface of the mesoporous particles as a process competitive to the pore filling. The crystalline nanoparticles form a hard protective coating on the outer surface of the larger spherical MCM-48 particles resembling hedgehog-like core−shell particles composed of an inner ordered mesoporous matrix and a hard nanosized silicon carbide coating. For SBA-15 it is shown that in the early stages of the CVI process at 1118 K, an ultrathin coating is produced that mainly consists of silicon oxycarbide. Subsequently, X-ray amorphous SiC is formed on top of this coating. In SBA-15, along with the formation of the coating, the pore size decreases from 5.5 to 3.0 nm, but further deposition leads to inhomogeneous coatings, and pore blocking and crystalline β-SiC particles are detected on the outer surface of the porous matrix by means of dark field transmission electron microscopy and wide-angle X-ray diffraction. The CVI process results in a significant enhancement of the thermal stability of SBA-15 even for very small degrees of filling.

Details

einblenden:
ausblenden:
Sprache(n): eng - English
 Datum: 2003-08-082004-06-292004-07-01
 Publikationsstatus: Erschienen
 Seiten: 12
 Ort, Verlag, Ausgabe: -
 Inhaltsverzeichnis: -
 Art der Begutachtung: Expertenbegutachtung
 Identifikatoren: DOI: 10.1021/cm034737
 Art des Abschluß: -

Veranstaltung

einblenden:

Entscheidung

einblenden:

Projektinformation

einblenden:

Quelle 1

einblenden:
ausblenden:
Titel: Chemistry of Materials
  Kurztitel : Chem. Mater.
Genre der Quelle: Zeitschrift
 Urheber:
Affiliations:
Ort, Verlag, Ausgabe: Washington, D.C. : American Chemical Society
Seiten: - Band / Heft: 16 (15) Artikelnummer: - Start- / Endseite: 2869 - 2880 Identifikator: ISSN: 0897-4756
CoNE: https://pure.mpg.de/cone/journals/resource/954925561571