Rationalizing inter- and intracrystal heterogeneities in dealuminated acid mordenite zeolites by stimulated Raman scattering microscopy correlated with super-resolution fluorescence microscopy.
Dealuminated zeolites are widely used acid catalysts in research and the chemical industry. Bulk-level studies have revealed that the improved catalytic performance results from an enhanced molecular transport as well as from changes in the active sites. However, fully exploiting this information in rational catalyst design still requires insight in the intricate interplay between both. Here we introduce fluorescence and stimulated Raman scattering microscopy to quantify subcrystal reactivity as well as acid site distribution and to probe site accessibility in the set of individual mordenite zeolites. Dealumination effectively introduces significant heterogeneities between different particles and even within individual crystals. Besides enabling direct rationalization of the nanoscale catalytic performance, these observations reveal valuable information on the industrial dealumination process itself.
Department of Chemistry, Faculty of Sciences, KU Leuven , 3001 Heverlee, Belgium.
Kuan-Lin
KL
Liu
Alexey V
AV
Kubarev
Jordi
J
Van Loon
Hiroshi
H
Uji-i
Dirk E
DE
De Vos
Johan
J
Hofkens
Maarten B J
MB
Roeffaers
Raman microscopy; dealumination; mordenite; single-molecule microscopy; stimulated Raman scattering; super-resolution fluorescence microscopy