Vanadium silicalite-1 nanoparticles deposition onto the mesoporous walls of SBA-15. Mechanistic insights from a combined EPR and Raman study.

Autor: Chiesa M; Dipartimento di Chimica IFM, Università di Torino and NIS, Nanostructured Interfaces and Surfaces Centre of Excellence,via P. Giuria 7, 10125, Torino, Italy., Meynen V, Van Doorslaer S, Cool P, Vansant EF
Jazyk: angličtina
Zdroj: Journal of the American Chemical Society [J Am Chem Soc] 2006 Jul 12; Vol. 128 (27), pp. 8955-63.
DOI: 10.1021/ja061630p
Abstrakt: Continuous Wave (CW) and pulsed Electron Paramagnetic Resonance (EPR) spectroscopy in conjunction with Raman spectroscopy are used to investigate the properties of Vanadium Silicalite-1 (VS-1) nanoparticles dispersed onto the mesoporous walls of SBA-15 silica. The properties of the deposited zeolite nanoparticles are found to be remarkably different from those of the full grown VS-1 zeolite. Monitoring of the local VO(2+) environment in the noncalcined nanoparticles in SBA-15 reveals that, in contrast to the full grown zeolite case, these sites are highly hydrophilic. Also, the stability of the TPAOH template is found to be affected by acidification of the nanoparticles. These results promise to be of great importance in elucidating the formation mechanism of TPAOH-templated zeolitic nanoparticles and their incorporation in mesoporous silica materials.
Databáze: MEDLINE