Responsive Pore Architecture in Microporous Metal–Organic Frameworks for Efficient Alkane Isomer Separation

Adsorptive separation offers significant potential for energy-efficient hydrocarbon separations; however, the underlying adsorption mechanisms remain limited. Here, we introduce pillared microporous metal–organic frameworks (MOFs), [Zn2(pzdc)(tz)] (pzdc = 3,5-pyrazoledicarboxylate, tz = tetrazole), featuring thermo- and guest-responsive pore architectures for the effective separation of alkane isomers. The functionalization of the tetrazole pillars with -NH2 or −CH3 groups imparts dynamic temperature-dependent rotational behavior, enabling the pore structures to adapt to guest molecules under varying thermal conditions. The responsive pore structures not only affect the adsorption capacity but also the diffusion behavior of alkane isomers, resulting in higher uptakes but lower diffusion rates at 323 K compared to 303 K. Moreover, the temperature-induced structural reorganization enhanced the separation efficiency, as validated through kinetic diffusion measurements and multicomponent breakthrough experiments, delivering a productivity of 31.4 L kg–1 for premium gasoline (RON ≥ 92). In situ single-crystal X-ray diffraction at different temperatures and temperature-dependent powder X-ray diffraction (XRD) experiments provided molecular-level insights into the adsorption mechanism and the temperature-dependent behavior of the pore channels in response to guest molecules.