Pore-Confined Carbonic Anhydrase in a Nanoporous Covalent Framework Membrane for Cooperative CO2 Capture Enhancement

Nanoporous functional polymers provide opportunities to couple molecular transport and catalysis within confined environments. Here, a carbonic anhydrase-immobilized nanoporous covalent framework membrane (CA/NCF) was developed as a catalytic platform for promoting CO₂ absorption in potassium carbonate solutions. The membrane was combined with piperazine (PZ), resulting in a cooperative enhancement in CO₂ uptake beyond that achieved by either PZ or CA alone. The results suggest that the nanoporous framework creates a confined catalytic environment that facilitates local CO₂ hydration, while PZ enhances reactive CO₂ transport in the carbonate phase. The interplay between pore confinement, carbonate buffering, and amine speciation governs reactive CO₂ availability, with the cooperative effect becoming increasingly significant at higher carbonate concentrations. These findings highlight the potential of functional nanoporous polymer membranes as catalytic platforms for intensified carbon capture processes.