Microporous solids are famous for their high surface area and pore size at the molecular scale, which are crucial for the applications of adsorption, separation and catalysis. An ideal porous solid would simultaneously have a high surface area and nanopores with the desired opening size. However, due to the uncontrollable reaction process of porous organic frameworks (POFs), the acquisition of such a solid is still technically limited. Herein, we reported a simple but platform-wide pore partition strategy to improve the porosity of porous aromatic frameworks (PAFs) in two aspects. This strategy was achieved by introducing a partition unit with flexible linkage to segment the original voids of PAFs into multiple micropore domains. The obtained partitioning PAFs have 130%-217% increments in surface area due to the creation of extra accessible surfaces while the pores are segmented into smaller ones. Notably, the partitioning PAFs showed significantly increased adsorption capacity for CO2 due to their improved surface area. At the same time, the narrowed pore size allowed selective capture of dye molecules by their size differences. Similar to their parent PAFs, the partitioning PAFs retained their high stability in harsh environments. A simple and universal pore partition strategy will be an important step in improving PAF porosity to desired functions.
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