Click-Based Porous Ionic Polymers with Intercalated High-Density Metalloporphyrin for Sustainable CO₂ Transformation

The development of advanced charged polymers with multifunctionality for heterogeneous catalysis is glamorous but still challenging. Herein, on the basis of function-oriented design philosophy, a series of metalloporphyrin-based porous ionic polymers (PiPs) were first synthesized through a facile and green method via Debus–Radziszewski reaction following click-chemistry principles. Benefiting from the enhancement of rigidity and contortion of the framework, these charged polymers presented improved specific surface area with hierarchical porous structures. The in situ polymerization method also endows them with extremely high density of biactive sites, anion tunability, and good CO₂/N₂ adsorptive selectivity. As a result, they exhibited excellent catalytic performance, robust recyclability, and good substrate expansibility in the solvent-free synthesis of cyclic carbonates from epoxides and CO₂ even at ambient conditions. Exhilaratingly, CoTPP-PiP­(Br) could smoothly catalyze this reaction by using simulated flue gas (15% CO₂ in 85% N₂, v/v) as a raw material under mild conditions. Thus, these functional PiPs diversified the types of porous polymers and provided a promising opportunity for the industrial synthesis of valuable cyclic carbonates from real-world CO₂.