Mechanochemistry Enables Targeted Synthesis of Mixed-Metal Microporous Metal-Organic Frameworks Using Pre-Assembled Precursors

Ball milling mechanochemistry enables enables targeted, rapid synthesis of mixed-metal metal-organic frameworks (MOFs) with controllable stoichiometric composition. Specifically, the use of ball milling enabled the use of pre-assembled coordination polymers of zinc, magnesium, nickel(II) and cobalt(II) as precursors in an innovative mechanochemical strategy for the deliberate assembly of mixed-metal MOF-74 materials comprised of pairs of transition of main group metals in a pre-determinmed 1:1 stoichiometric ratio, including ZnMg-, ZnCo, ZnCu, MgZn-, MgCo-, MgCa-, NiZn-,NiMg-, NiCo-, CoZn-, CoMg- and CoCu-MOF-74. While this is the first example of target-oriented MOF synthesis using mechanochemistry, it also provides an entry to controlling the stoichiometric composition of mixed-metal frameworks.