Pressure-induced hydration and cation migration in a Cs+ exchanged gallosilicate zeolite LTL

Synchrotron X-ray powder diffraction study at ambient and high pressures

Donghoon Seoung, Yongjae Lee, Sun Jin Kim, Hyun Hwi Lee, Docheon Ahn, Nam Soo Shin, Thomas Vogt, Yongjae Lee

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The ambient and high pressure structures of a partially cesium-exchanged K-gallosilicate with a zeolite LTL framework topology (Cs0.65K 0.35-GaSi-LTL) was studied using synchrotron X-ray powder diffraction. In contrast to the cation distribution present in the aluminosilicate analogues, the larger cesium cations replace part of the potassium cations in the narrow 8-ring channel as well as in the main 12-ring channel of the gallosilicate LTL. Under hydrostatic pressures mediated by a pore-penetrating alcohol and water mixture, anomalous compression behavior is observed with a slight increase in the unit cell volume upon initial compression, i.e., 0.15% expansion at 0.44 GPa. This is the result of the continuous increase of the a-axis length up to 2 GPa and is found to be related to the gradual pressure-induced hydration (PIH) occurring inside the main 12-ring channel, where the water content increases from 15.9(1) H2O at ambient conditions to 26.7(1) H2O per formula unit at 2.83 GPa. During PIH, part of the cesium cations along the main 12-ring channel migrate into the narrow 8-ring channel. Compared to the structural changes observed in K-GaSi-LTL, the degree of pressure-induced hydration and the accompanying cation migration is found to be diminished in Cs0.65K0.35-GaSi- LTL.

Original languageEnglish
Pages (from-to)75-82
Number of pages8
JournalMicroporous and Mesoporous Materials
Volume136
Issue number1-3
DOIs
Publication statusPublished - 2010 Dec 1

Fingerprint

Zeolites
Synchrotrons
Hydration
X ray powder diffraction
hydration
Cations
synchrotrons
Positive ions
Cesium
cations
cesium
rings
diffraction
x rays
Aluminosilicates
Hydrostatic pressure
hydrostatic pressure
Water content
moisture content
Potassium

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials

Cite this

Seoung, Donghoon ; Lee, Yongjae ; Kim, Sun Jin ; Lee, Hyun Hwi ; Ahn, Docheon ; Shin, Nam Soo ; Vogt, Thomas ; Lee, Yongjae. / Pressure-induced hydration and cation migration in a Cs+ exchanged gallosilicate zeolite LTL : Synchrotron X-ray powder diffraction study at ambient and high pressures. In: Microporous and Mesoporous Materials. 2010 ; Vol. 136, No. 1-3. pp. 75-82.
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Pressure-induced hydration and cation migration in a Cs+ exchanged gallosilicate zeolite LTL : Synchrotron X-ray powder diffraction study at ambient and high pressures. / Seoung, Donghoon; Lee, Yongjae; Kim, Sun Jin; Lee, Hyun Hwi; Ahn, Docheon; Shin, Nam Soo; Vogt, Thomas; Lee, Yongjae.

In: Microporous and Mesoporous Materials, Vol. 136, No. 1-3, 01.12.2010, p. 75-82.

Research output: Contribution to journalArticle

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T1 - Pressure-induced hydration and cation migration in a Cs+ exchanged gallosilicate zeolite LTL

T2 - Synchrotron X-ray powder diffraction study at ambient and high pressures

AU - Seoung, Donghoon

AU - Lee, Yongjae

AU - Kim, Sun Jin

AU - Lee, Hyun Hwi

AU - Ahn, Docheon

AU - Shin, Nam Soo

AU - Vogt, Thomas

AU - Lee, Yongjae

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