Prof. De Mendoza ( Institute of Chemical Research of Catalonia (ICIQ)) and his research team have synthesised unique octahedral and icosahedral anionic UOFs (Uranyl Organic Frameworks) from calixarenes, carboxylates and uranyl at room temperature.
Unlike most metallocages reported to date, the metals in these nanoscopic assemblies are not located at the corners or the edges of the resulting polyhedra but on the faces instead, acting both as a gluing element for the assembly of the components and a functional key substructure.
This novel arrangement, published in Nature Communications, allows host-guests interactions inside the cage and encapsulation of polycationic or electron deficient molecules.
The size of the calixarenes defines and dictates the shape and the size of the resulting globular assemblies in an univocal fashion:
6 calixarene subunits promote self-assembly into hexameric cages with an available spherical volume of ca. 940 Å3. 12 calixarene subunits promote self-assembly into icosahedral structures with an available spherical volume of more than 7000 Å3.
These anionic polyhedra have interesting photoluminescent, photoelectric and photocatalytic properties that can lead to efficient degradation of organic molecules, including pollutants, under UV irradiation.
The giant regular polyhedra shown above is the Featured Image of today's Nature Communications.