Abstract
Highly b-oriented, closely packed, MFI zeolite films are prepared on seeded stainless-steel plates using organic template-free, secondary growth solutions, containing aluminum sulfate as a crystallization agent. The number of a-oriented twin crystals is significantly reduced, and even eliminated, simply by restricting the pH value of the secondary growth solution to the narrow range of 11.1–11.3. Values of pH can be adjusted through the controlled addition of (NH 4 ) 2 SO 4 or H 2 SO 4 to secondary growth solutions of the composition (1 SiO 2 :0.57 NaOH:137.5 H 2 O:0.0050 (Al 2 (SO 4 ) 3 ⋅18 H 2 O)) or by simply decreasing the molar composition of NaOH with no extra additives.
Original language | English (US) |
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Pages (from-to) | 2519-2523 |
Number of pages | 5 |
Journal | Angewandte Chemie - International Edition |
Volume | 58 |
Issue number | 8 |
DOIs | |
State | Published - Feb 18 2019 |
Keywords
- MFI zeolite
- b-oriented
- pH effect
- secondary growth
- template-free
ASJC Scopus subject areas
- Catalysis
- Chemistry(all)