Self-condensation-assisted chemical vapour deposition growth of atomically two-dimensional MOF single-crystals.

Two-dimensional metal-organic frameworks (MOFs) have a wide variety of applications in molecular separation and other emerging technologies, including atomically thin electronics. However, due to the inherent fragility and strong interlayer interactions, high-quality MOF crystals of atomic thickness, especially isolated MOF crystal monolayers, have not been easy to prepare. Here, we report the self-condensation-assisted chemical vapour deposition growth of atomically thin MOF single-crystals, yielding monolayer single-crystals of poly[Fe(benzimidazole)] up to 62 μm in grain sizes.

Self-Templated Assembly of Au /Ag -Thiolate Sheets with Central Holes.

Composite crystalline sheets of Au /Ag -thiolate with central holes are achieved by co-assembly of Ag -thiolate and Au -thiolate in one-pot without sacrificial template. Both Ag -thiolate and Au -thiolate can separately assemble to lamellar sheets with similar structures, which makes their co-assembly possible, while the differences in their assembly pathways make the co-assembly processes highly dynamic and complex. First, a core@shell structure with Ag -thiolate at the core was formed upon the mixing of the two, then the core@shell structure transformed to a hole@shell structure by dissociation of the core.

Kinetic Study on the Self-Assembly of Au(I)-Thiolate Lamellar Sheets: Preassembled Precursor vs Molecular Precursor.

Molecular self-assembly has played an important role in nanofabrication. Due to the weak driving forces of noncovalent bonds, developing molecular nanoassemblies that have both robust preparation conditions and stable structure is a challenge. In our previous work, we have developed a reversible self-assembly system of Au(I)-thiolate coordination polymer (ATCP) to form colloidal lamellar sheets and demonstrated the high tailorability and stability of their structures, as well as their promising applications in gold nanocluster/nanoparticle fabrication and UV light shielding.

Manipulation of Inorganic Atomic-Layer Networks by Solution-Phase Co-assembly.

Homogeneous 2D lamellar assemblies of Au thiolate coordination polymer (ATCP) were obtained by two-ligand co-assembly. The orbital levels and the bandgap of the 2D Au -S network in the centre of the lamellae can be continuously tuned by means of the capping ligands on both sides, to give a new type of inorganic-organic composite semiconductor, the band structure of which can be easily tuned by low-temperature solution-phase co-assembly. Furthermore, the chemical reactivity of these ATCP co-assemblies also proved to be strongly dependent on the organic substituents, with well-tuneable transformation rates to gold nanoparticles.