MOF-reactors · Metal-Organic Frameworks as Chemical Reactors for the Synthesis of Well-Defined Sub-Nanometer Metal Clusters

Humankind advancement is connected to the use and development of metal forms. Recent works have unveiled exceptional properties –such as luminescence, biocompatibility, antitumoral activity or a superlative catalytic activity– for small aggregations of metal atoms, so–called sub–nanometer metal clusters (SNMCs). Despite this importance, the gram-scale synthesis of structurally and electronically well–defined SNMCs is still far from being a reality.The present proposal situates at the centre of such weakness and aims at making a breakthrough step-change on the use of metal-organic frameworks (MOFs) as chemical reactors for the in–situ synthesis of stable ligand-free SNMCs with such unique properties. This challenging synthetic strategy, which is assisted by striking published and inedited preliminary results, has solid foundations. Firstly, the design and large-scale preparation of cheap and novel families of highly robust and crystalline MOFs with tailor-made functional channels to be used as chemical reactors. Secondly, the application of solid-state post-synthetic methods to drive the multigram-scale preparation of unique ligand-free homo- and heterometallic SNMCs, which are, in the best-case scenario, very difficult to be obtained and stabilised outside the channels. Last but not least, single-crystal X-Ray diffraction will be used as the definitive tool for the characterisation, at the atomic level, of such ultrasmall species offering unprecedented snapshots about their real structures and formation mechanisms.The ultimate goal will be upscaling this synthetic strategy aiming at the large-scale fabrication of SNMCs and their industrial application will be then evaluated. A successful achievement of all the aforementioned objectives of this ground-breaking project would open new routes for the use of MOFs as chemical reactors to manufacture, at competitive prices, MOF-driven, structurally and electronically well–defined, ligand–free SNMCs in a multigram-scale.