Synergistic High‐Connectivity and Nonplanar Conformation Generates a Stable Hydrogen‐Bonded Organic Framework for Benchmark Methanol‐to‐Olefin Product Separation

ABSTRACT Hydrogen‐bonded organic frameworks (HOFs) are promising porous materials, yet their development is hindered by an inherent trade‐off between structural stability and functional site accessibility. Conventional stabilization strategies relying on extensive π–π stacking inevitably shield aromatic surfaces, compromising adsorption performance. Herein, we report a synergistic design strategy that integrates high hydrogen‐bonding connectivity with inherently nonplanar molecular conformations to overcome this challenge. The strategically designed tetraisophthalate linker, featuring a hexamethylbiphenyl core, adopts a nonplanar conformation that suppresses extended π–π stacking, while its eight carboxylic acid groups form a dense hydrogen‐bonded network ensuring framework robustness. The resulting HOF‐ZJNU‐10 exhibits a high BET surface area (2500 m 2 g −1 ), exceptional stability, and crucially, fully accessible aromatic surfaces lining the pore channels. This unique combination enables outstanding methanol‐to‐olefins (MTO) product purification, delivering polymer‐grade ethylene and propylene with record‐high productivity. This work establishes a general blueprint for decoupling stability from functional site masking in HOFs.