Reticular Design of Precise Linker Installation into a Zirconium Metal-Organic Framework to Reinforce Hydrolytic Stability

Reticular chemistry allows for the rational assembly of metal-organic frameworks (MOFs) with designed structures and desirable functionalities for advanced applications. However, it remains challenging to construct multi-component MOFs with unprecedented complexity and control through insertion of secondary or ternary linkers. Herein, we demonstrate that a Zr-based MOF, NU-600 with a (4,6)-connected she topology, has been judiciously selected to employ a linker installation strategy to precisely insert two linear linkers with different lengths into two crystallographically distinct pockets in a onepot, de novo reaction. We reveal that the hydrolytic stability of these linker-inserted MOFs can be remarkably reinforced by increasing the Zr6 node connectivity, while maintaining comparable water uptake capacity and pore-filling pressure as the pristine NU-600. Furthermore, introducing hydrophilic -OH groups into the linear linker backbones to construct multivariate MOFs can effectively shift the porefilling step to lower partial pressures. This methodology demonstrates a powerful strategy to reinforce the structural stability of other MOF frameworks by increasing the connectivity of metal nodes, capable of encouraging developments in fundamental sciences and practical applications.

Automated summary

In this study, a Zr-based MOF, NU-600, was used to demonstrate the construction of multi-component MOFs with unprecedented complexity and control by inserting two linear linkers with different lengths into distinct pockets. It was found that increasing the connectivity of Zr6 nodes remarkably reinforced the hydrolytic stability of these linker-inserted MOFs while maintaining their water uptake capacity and pore-filling pressure. Additionally, introducing hydrophilic -OH groups into the linkers effectively shifted the pore-filling step to lower partial pressures. This methodology provides a powerful strategy to enhance the structural stability of other MOF frameworks and promotes advancements in fundamental sciences and practical applications.