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.

金属有机框架（Metal–organic frameworks, MOFs）长期以来被广泛研究，因其结构可调且可应用于气体分离与催化领域，但可实现金属-配体π反馈键（π-backbonding）的相关体系仍较为罕见。本研究突破传统MOFs的研究范畴，以多孔配位笼（porous coordination cages, PCCs）作为模块化构筑单元，构建了高度可调的多孔盐类材料。通过在带电PCCs中引入配位不饱和、π碱性的钌位点，我们实现了一氧化碳的选择性可逆化学吸附（chemisorption）——这一特性在杂化多孔材料中极为少见。我们还证实，可将非多孔分子钌配合物作为电荷平衡抗衡离子（counterions）引入体系，由此得到孔隙率与吸附性能可定制的多孔材料。上述研究成果提出了一种兼具分子反应性与可调孔隙率的多孔盐设计策略，为下一代分离、传感与催化领域提供了极具潜力的发展路径。本研究将分子设计原理与材料功能特性有机结合，拓展了超越传统MOFs的自适应多孔材料的设计工具箱。