Sub-Angstrom Level Pore-Size Tuning in Porous Carbon Materials through Single-Step Carbonization of Precursors Rationally Designed through π-Conjugation Extension

Precise tuning of pore sizes in porous carbon materials at the sub-angstrom level remains a challenging task, mainly because of the uncontrollable structural rearrangement during high-temperature carbonization. Here, we report the design and synthesis of porous carbon materials derived from planar triazine-based precursors. These precursors inherently exhibit two-dimensional architectures, which translate into the formation of sheet-like porous carbon materials. Notably, thermal cross-linking of the precursors prior to carbonization enables precise sub-angstrom pore size tuning (4.01 Å → 4.28 Å → 4.56 Å) through systematic extension of the <i>p</i>-phenylene linkages. Among the obtained porous carbon materials, the porous carbon material with precisely tuned 4.56 Å pores showed high CO₂/CH₄ selectivity.