There has been a recent trend of designing nanomaterials in silico (inside a computer) prior to synthesis. Given that computers can potentially design thousands or millions of materials in short period of time, one can in principle significant amount of materials discovery time by using rational search algorithm via computational tools. Unfortunately, it is extremely difficult to design complicated composite materials given that the interface between material A and material B is unclear and ill-suited to be

An algorithm study by KAIST research team reported in Nature Communications presents the clue to find the perfect pairs. The team led by Professor Ji-Han Kim at the Department of Chemical and Biomolecular Engineering developed a joint computational and experimental approach to rationally design MOF@MOFs, a composite of MOFs where a MOF is grown on a different MOF.

Professor Kim's team in collaboration with UNIST noted that metal node of one MOF can coordinately bond with the linker of a different MOF and the precisely matched interface configurations at atomic and molecular level can enhance the likelihood of synthesizing MOF@MOFs.

They screened thousands of MOFs and identified optimal MOF pairs that can seamlessly connect to one another by taking advantage of the fact that the metal node of one MOF can from coordination bonds with the linkers of the second MOF. Six pairs predicted from the computational algorithm successfully grew into single crystals.

This computational workflow can readily extend into other classes of materials and can lead to rapid exploration of the composite MOFs space for accelerated materials development. Even more, the workflow can enhance the likelihood of synthesizing MOF@MOFs in the form of large single crystal, and thereby demonstrated the utility of rationally designing the MOF@MOFs

Professor Kim said, "This workflow can enhance the likelihood of synthesizing MOF@MOFs in the form of large single crystal, demonstrating the utility of rationally designing the MOF@MOFs." This study is the first algorithm of predicting synthesis of composite MOFs, to the best of their knowledge. Professor Kim said, "The number of predicted pairs can increase even more with a more general 2D lattice matching, and it is worth investigating in the future."