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Updated: Jul 10, 2026
08:26
Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route
Published on: April 3, 2016
First principles studies on boron sites in zeolites
Federica Trudu1, Gloria Tabacchi, Aldo Gamba
1Dipartimento di Scienze Chimiche ed Ambientali, University of Insubria at Como, and INSTM udr Como, Via Lucini 3, I-22100 Como, Italy.
The Journal of Physical Chemistry. A
|October 20, 2007
Summary
Protonated boron-containing zeolites (boralites) feature a flexible, loosely bound acid site, impacting their thermal behavior. These mild acid catalysts show promise for catalytic applications.
Area of Science:
- Materials Science
- Computational Chemistry
- Catalysis
Background:
- Boron-containing zeolites (boralites) are investigated for their catalytic properties.
- Understanding the nature of acid sites in boralites is crucial for catalyst design.
Purpose of the Study:
- To systematically investigate the structure and properties of protonated and nonprotonated boralites using computational methods.
- To analyze the minimum energy structures and finite temperature behavior of model boron sodalites.
Main Methods:
- Periodic density functional theory (DFT) approximations were employed.
- Analysis of minimum energy structures and vibrational properties.
- Investigation of thermal behavior at finite temperatures.
Main Results:
- A silanol Si-OH group loosely linked to a planar BO(3) structure was identified as the acid site in protonated boralites.
- A tetrahedral BO(4) site was predicted for sodium-containing boralites.
- Calculated properties align with experimental data, showing framework flexibility and thermal effects.
Conclusions:
- Protonated boralites act as mild acid catalysts with significant framework flexibility.
- The loosely bound acid site leads to pronounced thermal effects.
- Comparison with Al and Ga zeolitic acid sites highlights unique characteristics of boralites.
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