Aperture Fine‐Tuning in Cage‐Like Metal–Organic Frameworks via Molecular Valve Strategy for Efficient Hexane Isomer Separation

Cage‐like metal–organic frameworks (MOFs) are promising for hexane isomer separation, but their aperture sizes difficult to control precisely. Herein, a molecular valve strategy is proposed fine‐tune the of cage‐like MOFs, thereby enhancing separation performance isomers. Three novel isostructural namely Cu‐MO 4 ‐TPA, synthesized using different oxometallate anions (MO 2− , M = Cr, Mo, and W) ligand tri(pyridin‐4‐yl)amine (TPA). The induce varying degrees twisting in TPA ligand, leading sub‐angstrom tuning size MOFs. materials can separate isomers based on degree branching, with smallest material (Cu‐MoO ‐TPA) showing sieving di‐branched Adsorption isotherms, kinetic, breakthrough measurements, Monte Carlo, density functional theory calculations confirm differences result superior by Cu‐MoO ‐TPA. results demonstrate effectiveness fine‐tuning MOF selective applications.