A Rod‐Packing Hydrogen‐Bonded Organic Framework with Suitable Pore Confinement for Benchmark Ethane/Ethylene Separation

Abstract For the separation of ethane from ethylene, it remains challenging to target both high C 2 H 6 adsorption and selectivity in a C 2 H 6 ‐selective material. Herein, we report a reversible solid‐state transformation in a labile hydrogen‐bonded organic framework to generate a new rod‐packing desolvated framework (ZJU‐HOF‐1) with suitable cavity spaces and functional surfaces to optimally interact with C 2 H 6 . ZJU‐HOF‐1 thus exhibits simultaneously high C 2 H 6 uptake (88 cm 3 g −1 at 0.5 bar and 298 K) and C 2 H 6 /C 2 H 4 selectivity (2.25), which are significantly higher than those of most top‐performing materials. Theoretical calculations revealed that the cage‐like cavities and functional sites synergistically “match” better with C 2 H 6 to provide stronger multipoint interactions with C 2 H 6 than C 2 H 4 . In combination with its high stability and ultralow water uptake, this material can efficiently capture C 2 H 6 from 50/50 C 2 H 6 /C 2 H 4 mixtures in ambient conditions under 60 % RH, providing a record polymer‐grade C 2 H 4 productivity of 0.98 mmol g −1 .