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This content will become publicly available on October 22, 2026

Title: Customizable Aperture Geometry in Metal–Organic Frameworks for Kinetic Hydrocarbon Separation
Precise control of aperture dimensions is crucial in adsorptive separations of hydrocarbons, as it directly affects key parameters such as selectivity, capacity, diffusion, and recyclability. The development of metal-organic frameworks (MOFs) has enabled the fine-tuning of local pore environments to address important hydrocarbon separations. However, customizing aperture geometry to tune kinetic separation performance remains challenging. Here, we deploy a mixed-linker synthesis strategy, combining long and short linkers on fcu net Zr-MOFs with equilateral triangular apertures to construct isoreticular multivariate MOFs, NU-415 and NU-416, with tailored isosceles triangular apertures suitable for the separation of hexane isomers. Sorption, liquid batch separa-tion and X-ray diffraction measurements demonstrate significantly improved selectivity, capacity, stability and recyclability of NU-415 and NU-416 compared with Zr-muconate and MOF-801. Notably, both NU-415 and NU-416 achieve uptake capacities of 2.2 mmol g-1 in 1 minute with a n-hexane to 2,2-dimethylbutane selectivity over 200 in equimolar ternary mixture at ambient conditions, comparable to leading reported materials. Mechanistic studies confirm that separation performance is predominantly governed by significant kinetic differences rather than by thermodynamics. The successful customization of aperture geometry not only enables superior linear to monobranched hexane selectivity in NU-415, but also demonstrates the mixed-linker synthesis strategy as a promising solution for precise and predictable pore architecture control in MOFs.  more » « less
Award ID(s):
2119433
PAR ID:
10648730
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
147
Issue:
42
ISSN:
0002-7863
Page Range / eLocation ID:
38647 to 38656
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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