Ordered microporous layered lanthanide 1,3,5-benzenetriphosphonates pillared with cationic organic molecules

Area of Science:

• Materials Science
• Inorganic Chemistry
• Crystallography

Background:

• Lanthanide 1,3,5-benzenetriphosphonates are crystalline materials with potential applications.
• Pillared-layer structures are key to creating porous frameworks.
• Understanding the role of organic linkers is crucial for material design.

Purpose of the Study:

• To synthesize novel isomorphous pillared-layer lanthanide phosphonates.
• To elucidate the structural role of organic pillars (bpy and dbo).
• To investigate the porosity and stability of the resulting materials.

Main Methods:

• Synthesis of lanthanide 1,3,5-benzenetriphosphonates with bpy and dbo pillars.
• Ab initio crystal structure solution using synchrotron X-ray powder diffraction.
• Gas adsorption analysis (N2, CO2, H2) to confirm microporosity.
• Thermal analysis under vacuum to study water removal.

Main Results:

• Novel isomorphous pillared-layer lanthanide phosphonates (LnBP-bpy, LnBP-dbo) were successfully prepared.
• Organic pillars were identified as cationic molecules, not neutral ligands.
• LnBP-dbo phases showed ordered interlayer water, removable upon heating.
• Confirmed microporosity across various gas adsorption studies.

Conclusions:

• The study presents unprecedented microporous layered metal phosphonates pillared with cationic molecules.
• The findings offer new strategies for designing ordered microporous materials.
• The cationic nature of the pillars and ordered water molecules are key structural features.