One Flexible Metal–Organic Framework with Guest‐Adaptive Rotational Valve for Gas Separation
Pengtao Guo, Jia Fu, Bo Xue, Ting Wang, Lun Yang, Yunpan Ying, Qing‐Yuan Yang, Dahuan Liu
Abstract
Abstract The dynamic structural properties of flexible metal–organic frameworks (MOFs) endow them with a unique ability to recognize guest molecules. However, designing a flexible MOF that is sensitive to guest molecules and can recognize one target molecule from gas mixtures that have weak interactions with the adsorbent remains a challenge. Herein, a “guest‐adaptive rotational valve” strategy is proposed that introduces a guest‐adaptive rotating 3D linker into a 1D confined channel of locally flexible MOF (CoNi‐TED) to address this challenging separation. Under the collaboration of adaptive rotating linkers and dense open metal sites, CoNi‐TED displays record CH 4 /N 2 selectivity (23.5) and CH 4 /N 2 uptake ratio (8.64) at 298 K and 1 bar. Breakthrough experiments and pressure swing adsorption (PSA)simulations show that it can produce CH 4 with a good balance between purity and recovery. Besides, it shows high structural stability and can be scaled up to a kilogram scale under simple and gentle synthesis conditions, rendering it a new benchmark adsorbent for natural gas purification.