Manipulation of Charged Porous Cages as Tunable Platforms for Strong Gas Adsorption

Metal–organic frameworks (MOFs)
have long been explored
for their tunable structures and applications in gas separation and
catalysis, yet systems capable of engaging in metal-to-ligand π-backbonding
remain scarce. Expanding beyond MOFs, our study leverages porous coordination
cages (PCCs) as modular building blocks to construct highly tunable
porous salts. By incorporating coordinatively unsaturated, π-basic
ruthenium sites within charged PCCs, we achieve selective and reversible
carbon monoxide chemisorption, a property rarely observed in hybrid
porous materials. We further demonstrate that nonporous molecular
ruthenium complexes can be incorporated as charge-balancing counterions,
yielding materials with tailored porosities and adsorption properties.
These findings introduce a strategy for designing porous salts that
integrate molecular reactivity with tunable porosity, offering promising
avenues for next-generation separations, sensing, and catalysis. Our
approach bridges molecular design principles with material functionality,
expanding the toolkit for designing adaptive porous materials beyond
traditional MOFs.