Humidity‐Resistant Methane Single‐Molecule Traps for Efficient Separation of Coal‐Bed Methane

Abstract The rational design of efficient adsorbents for methane capture from coal‐bed methane (CBM) is crucial for both energy utilization and environmental protection. In this study, a novel “methane single‐molecular trap” (MSMT) architecture is reported within a metal–organic framework (MOF) for CH 4 capture from CBM, in which each MSMT is designed as a unique space that can accommodate only a single CH 4 molecule, surrounded by open metal sites (OMSs) and adjacent hydrophobic alkyl groups. The obtained adsorbent, MSMT‐NKMOF‐1, exhibits efficient separation of CH 4 /N 2 , achieves a dynamic selectivity of 9.2 and a CH 4 productivity of 22.6 L kg −1 at 298 K and 1 bar. Furthermore, this design shows impressive humidity resistance. Combined experimental and theoretical analyses reveal that the MSMT design not only eliminates the “desert” regions for traditional adsorbents—where strong functional sites are inaccessible—thereby enhancing the dynamic selectivity, but also prevents moisture interference. Additionally, MSMT‐NKMOF‐1 can be synthesized rapidly and environmentally friendly at room temperature, providing feasibility for industrial CBM purification. The work not only develops MSMT‐NKMOF‐1 as a promising adsorbent for CH 4 /N 2 separation, but also provides a generalizable guidance for the development of novel functional porous materials for related applications.