To control heterogeneous catalysis at atomic and electronic-level represents one of the most challenge research areas. Using metal-organic frameworks (MOFs) as hosts of metal nanoclusters, we could reach an atomic and electronic-level control of heterogeneous catalysts. MOFs, as novel template materials for the synthesis of metal nanoclusters, have great potentials for catalysis due to their structural diversity, flexibility and tailorability, as well as high porosity. Compared to zeolite, the chemical environment of each cage/cavity of MOFs can be controlled at atomic-level by using different organic linkers.
The MOFs with isoreticular structures are particularly interesting because they have exactly the same lattice structure, but different chemical compositions. These different organic linkers or metal ion nodes of MOFs results geometrically identical cages of different chemical environments. Nanoclusters, resident in these cages/cavities, would experience an atomic-level fine-tuned chemical environment, and thus exhibit different activity and selectivity in heterogeneous catalysis. During chemical conversion processes, reactants and reaction intermediates could also sense these chemical environments that could alter their adsorption energy and geometry, which will also affect the reaction activity and selectivity.
Program mentor: Wenyu Huang, assistant professor, Chemistry, Iowa State University