Chemically Stable Tetrazine-Based Porous Organic Cages with Post-Synthetic Modification via Inverse-Electron-Demand...

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Chemical Engineering

Background:

• Porous organic cages (POCs) are advanced porous materials with diverse applications.
• Existing POCs often suffer from limited chemical stability and functionalization challenges.
• Developing robust and tunable POCs is crucial for practical gas separation technologies.

Purpose of the Study:

• To design and synthesize novel tetrazine-based porous organic cages (POCs).
• To evaluate the gas adsorption and separation capabilities, particularly for SF6/N2.
• To explore post-synthetic modification and polymerization for enhanced stability and new material construction.

Main Methods:

• One-pot nucleophilic aromatic substitution for cage synthesis.
• Post-synthetic modification using inverse electron-demand Diels-Alder (iEDDA) reactions.
• iEDDA polymerization to create networked porous materials.

Main Results:

• A tetrazine-based POC (TC1) with high porosity (1157 m2/g) and excellent chemical stability was synthesized.
• TC1 demonstrated record-breaking SF6 adsorption capacity and selectivity for SF6/N2 separation.
• Functionalized cages (TC2, TC3) and networked materials (TC1-P1, TC1-P2) exhibited enhanced stability and tunable CO2/N2 selectivity.

Conclusions:

• Tetrazine-based POCs represent a stable and highly porous molecular platform.
• These materials show exceptional performance in SF6/N2 separation and potential for CO2 capture.
• The synthetic strategies enable tunable properties for advanced gas separation applications.