Polynuclear Rare-Earth Cluster-Directed Self-Assembly of Highly Porous Zeolite-like Metal-Organic Frameworks with Methane Storage Property

Due to their intrinsic structural features, the design and synthesis of a new type of zeolite-like metal-organic frameworks (ZMOFs) is highly desirable but challenging. Herein, solvothermal reactions between an angular dicarboxylate linker and rare-earth (RE) ions afforded two RE-MOFs, namely, Tb-ZMOF-2 and Tb-ZMOF-3, respectively. Structural analyses reveal that Tb-ZMOF-2 encompasses a novel [4(4)6(4)8(2)] cage, while Tb-ZMOF-3 contains nonanuclear (i.e., D6R) and hexanuclear (i.e., D4R) RE clusters simultaneously, subsequently resulting in two new zeolitic topologies. Thanks to its high surface area and pore volume, Tb-ZMOF-2 demonstrates considerably high gravimetric and volumetric methane storage working capacities.

Automated summary

The design and synthesis of a new type of zeolite-like metal-organic frameworks (ZMOFs) with intrinsic structural features is highly desirable but challenging. In this study, two rare-earth (RE)-MOFs, Tb-ZMOF-2 and Tb-ZMOF-3, were successfully obtained through solvothermal reactions. Structural analyses revealed the novel [4(4)6(4)8(2)] cage in Tb-ZMOF-2 and the simultaneous presence of nonanuclear (D6R) and hexanuclear (D4R) RE clusters in Tb-ZMOF-3, resulting in two new zeolitic topologies. Tb-ZMOF-2 demonstrated high gravimetric and volumetric methane storage working capacities due to its high surface area and pore volume.