A zeolite family with expanding structural complexity and embedded isoreticular structures

Area of Science:

• Materials Science
• Crystallography
• Chemistry

Background:

• Zeolites are crucial porous materials, but their synthesis typically relies on exploratory methods, hindering targeted material design.
• While millions of hypothetical zeolite structures exist, understanding their synthesis mechanisms remains a significant challenge.

Purpose of the Study:

• To develop a combined structure solution and prediction approach for targeted synthesis of novel, complex zeolites.
• To overcome limitations in zeolite discovery and enable the preparation of materials with desired properties.

Main Methods:

• Utilized electron diffraction to identify related structures and decipher their underlying structural 'coding'.
• Integrated structure solution with structure prediction to guide the synthesis of new zeolite families.
• Applied the method to determine the structure of zeolite ZSM-25 and predict/synthesize related complex zeolites (PST-20, PST-25).

Main Results:

• Determined the complex, previously unknown structure of zeolite ZSM-25, possessing the largest known unit-cell volume and selective CO2 adsorption.
• Successfully predicted and synthesized two more complex zeolites, PST-20 and PST-25, with significantly larger unit-cell volumes.
• Identified a family of related zeolites with the same symmetry but expanding unit cells, governed by novel structural principles termed 'embedded isoreticular zeolite structures'.

Conclusions:

• The developed approach successfully bridges structure prediction and synthesis for complex zeolites.
• This enables the targeted design and creation of advanced porous materials with tailored properties, such as selective CO2 adsorption.
• The discovery of embedded isoreticular zeolite structures offers new insights into zeolite structural relationships and expands the possibilities for materials discovery.