RESUMO
Arrays of alternating metallic nanostructures present hybrid properties, which are useful for applications in photonics and catalysis. Block copolymer films provide versatile templates for fabricating periodic arrays of nanowires. Yet, creating arrays with alternating compositions or structures requires different modifications of domains of the same kind. By controlling the penetration depth of metal precursors into the film we were able to impregnate different layers of copolymer cylinders with different metals. Capitalizing on the hexagonal packing of the cylinders led to simultaneous formation of nanowires with alternating compositions and periodic arrangement on the substrate after plasma etching. Selective deposition of nanoparticles on the film enabled creating alternating bare and decorated nanowires, as well as trimetallic nanowire arrays.
RESUMO
One tetrahedral and two trigonal prismatic cages with π-basic Au3(pyrazolate)3 faces were obtained by connection of pre-formed gold complexes via dynamic covalent imine chemistry. The parallel arrangement of the Au3(pyrazolate)3 complexes in the prismatic cages augments the interaction with π-acids, as demonstrated by the encapsulation of polyhalogenated aromatic compounds. The tetrahedral cage was found to act as a potent receptor for fullerenes. The structures of the three cages, as well as the structures of adducts with C60 and C70, could be established by X-ray crystallography.