Facile Synthesis of Ultrastable Porous Aromatic Frameworks by Suzuki-Miyaura Coupling Reaction for Adsorption Removal of Organic Dyes.

Porous aromatic frameworks (PAFs) with robust structure, high stability, and high surface area have attracted intense interest from scientists in diverse fields. However, there are still very few reports on the adsorption of organic dyes by PAFs. In this work, four new PAFs have been facilely synthesized by the polymerization of a tetrahedral-shaped (four-node) monomer with a series of three-node monomers through Suzuki-Miyaura coupling reactions. All the obtained materials possess hierarchical porous structures and show high thermal and chemical stability. The Brunauer-Emmett-Teller (BET) surface areas of these PAFs were determined to be 857 m2  g-1 for PAF-111, 526 m2  g-1 for PAF-112A, 725 m2  g-1 for PAF-112B, and 598 m2  g-1 for PAF-113. Rhodamine B was selected as a model organic dye to test the adsorption capacities of the obtained PAF materials. PAF-111 showed a maximum adsorption capacity of 1666 mg g-1 (167 wt %) for Rhodamine B, which is among the highest values reported to date for porous organic materials. It is noteworthy that PAF-111 could be reused in at least ten cycles under the adsorption conditions without any loss of adsorption capacity. Our study has revealed the great potential and advantages of PAFs as ultrastable adsorption materials for the removal of organic dyes.