Related Experiment Video
Updated: Aug 7, 2026
08:26
Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route
Published on: April 3, 2016
Adsorbate-Induced Reversible Changes in Zeolite ZEO-5 Attributed to Its Triple-Four-Silicate-Rings
Zihao Rei Gao1, Cristian Aristizabal-González2, Prerna3,4
1Institute for NanoBioTechnology & Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland, USA.
Angewandte Chemie (International Ed. in English)
|August 6, 2026
Summary
Extra-large pore zeolite ZEO-5 shows reversible structural changes upon adsorption of water and other polar molecules. This unique property enhances its performance in adsorptive separations, particularly for ammonia removal.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Extra-large pore zeolites possess unique structural characteristics compared to conventional zeolites.
- These structural features offer potential for advanced applications in adsorption and catalysis.
Purpose of the Study:
- To investigate the synthesis and adsorption properties of a novel low-framework-density zeolite, ZEO-5.
- To elucidate the structural transformations and underlying mechanisms governing ZEO-5's adsorption behavior.
Main Methods:
- Synthesis of ZEO-5 via interchain expansion, creating triple four-ring (t4r) units and 20-membered-ring pores.
- Characterization using synchrotron powder X-ray diffraction, porosimetry, in situ infrared spectroscopy, and solid-state nuclear magnetic resonance.
- Molecular simulations and structural modeling to explain observed phenomena.
Main Results:
- ZEO-5 exhibits a unique hydrophobic-to-hydrophilic transition during water adsorption with significant hysteresis.
- Structural degradation via Si─O─Si bond cleavage in t4r units was observed upon adsorption.
- Recalcination fully restored ZEO-5's original structure, demonstrating reversible adsorption-induced order-disorder transformation.
- Similar reversible behavior was noted with ammonia and alcohols.
Conclusions:
- ZEO-5 displays a reversible structural transformation triggered by polar molecule adsorption, a phenomenon linked to its strained t4r units.
- This unique property enhances ZEO-5's utility in adsorptive separations, showing high ammonia working capacity.
- The findings have broad implications for designing functional materials for separation technologies and pore functionalization.
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