Flexible three-dimensional diacetylene functionalized covalent organic frameworks for efficient iodine capture.

Area of Science:

• Materials Science
• Chemistry
• Environmental Science

Background:

• Functionalized covalent organic frameworks (COFs) are crucial for advanced applications but challenging to synthesize, especially 3D COFs adhering to specific topologies.
• Developing robust porous materials is essential for addressing environmental concerns like radioactive iodine contamination.

Purpose of the Study:

• To synthesize novel diamondyne-like 3D COFs (CPOF-2 and CPOF-3) with acetylene and diacetylene functionalities.
• To evaluate the performance of these COFs as adsorbents for volatile iodine capture.

Main Methods:

• Synthesis of two distinct 3D COFs (CPOF-2 and CPOF-3) using specific organic building blocks.
• Characterization of the COFs for crystallinity, porosity, and chemical stability.
• Testing the iodine uptake capacity of the synthesized COFs, particularly CPOF-3.

Main Results:

• Successful synthesis of highly crystalline, permanently porous, and chemically stable 3D COFs (CPOF-2 and CPOF-3).
• CPOF-3 demonstrated exceptional volatile iodine uptake capacity (5.87 g g⁻¹), surpassing most existing COF-based adsorbents.
• The functionalization with acetylene and diacetylene groups contributed to the high adsorption performance.

Conclusions:

• The study presents a new design strategy for creating high-performance iodine-loading porous materials.
• These functionalized 3D COFs offer a promising solution for mitigating radioactive iodine pollution from nuclear waste.