Sub-Angstrom Level Pore-Size Tuning in Porous Carbon Materials through Single-Step Carbonization of Precursors...

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Precise control over pore sizes in porous carbon materials at the sub-angstrom level is difficult due to structural changes during high-temperature carbonization.
• Existing methods struggle to achieve fine-tuning of pore dimensions, limiting applications in areas like gas separation.

Purpose of the Study:

• To design and synthesize novel porous carbon materials with precisely tuned sub-angstrom pore sizes.
• To investigate the relationship between precursor structure and resulting pore characteristics.
• To evaluate the gas separation performance of the synthesized materials, specifically CO2/CH4 selectivity.

Main Methods:

• Synthesis of planar triazine-based precursors with inherent two-dimensional architectures.
• Thermal cross-linking of precursors to control the extension of p-phenylene linkages.
• High-temperature carbonization to form sheet-like porous carbon materials.
• Characterization of pore sizes and evaluation of CO2/CH4 selectivity.

Main Results:

• Successfully synthesized sheet-like porous carbon materials from triazine-based precursors.
• Achieved precise sub-angstrom pore size tuning (4.01 Å → 4.28 Å → 4.56 Å) via controlled precursor modification.
• The porous carbon material with 4.56 Å pores demonstrated high CO2/CH4 selectivity.

Conclusions:

• Thermal cross-linking of triazine precursors offers a viable strategy for precise sub-angstrom pore size control in porous carbons.
• The developed materials show promise for efficient gas separation applications, particularly for CO2 capture.
• This approach overcomes limitations associated with structural instability during conventional carbonization.