Chiral plasmonic nanocrystals are promising materials for applications in enantioselective catalysis, DNA detection, and medical diagnosis. Herein, we demonstrate a simple and versatile strategy that produces plasmonic nanostructures with strong chiroptical responses by a chiral ligand mediated seeded growth approach. By modulation of the surface coverage of chiral ligands on Au nanotriangles, propeller-like structures with the growth of three arms on the tips of the triangles are produced with a high anisotropy factor. Finally, these Au chiral propellers can be used as substrates for the surface-enhanced Raman scattering (SERS) detection of chiral biomolecules, achieving chiral differentiation for enantiomers of biomolecules.

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Precise organization of matter across multiple length scales is of particular interest because of its great potential with advanced functions and properties. Here we demonstrate a simple yet versatile strategy that enables the organization of hydrophobic nanoparticles within the covalent organic framework (COF) in an emulsion droplet. The interfacial polymerization takes place upon the addition of Lewis acid in the aqueous phase, which allows the formation of COF after a crystallization process. Meanwhile, the interaction between nanoparticles and COF is realized by the use of amine-aldehyde reactions in the nearest loci of the nanoparticles. Importantly, the competition between the nanoparticle self-assembly and interfacial polymerization allows control over the spatial distribution of nanoparticles within COF. As a general strategy, a wide variety of COF-wrapped nanoparticle assemblies can be synthesized and these hybridized nanomaterials could find applications in optoelectronics, heterogeneous catalysis and energy chemistry.

Although self-assembly of binary nanocrystal mixtures into long-range ordered crystalline films with tunable lattice structures are well-known, it would be interesting to shape these binary nanocrystal supracrystals into faceted assemblies because it potentially provides the shape-dependent optical, electronic, and catalytic properties. Herein, we report the self-assembly of binary nanocrystal supracrystals with faceted morphologies from Fe3O4 and Au binary mixtures. The asymmetric crystal parameters in AlB2-type structure, a = b > c, favors one-dimensional (1D) self-assembly along the ⟨001⟩ direction, resulting in the formation of supraspindles and suprarods with 20 facets. For the symmetric cubic lattice system, like NaCl-type and NaZn13-type structures, truncated cube/octahedron with preferential exposed facets of (100) and (111) are produced. By contrast, for another cubic lattice of bcc-AB6, in which large nanocrystals are ordered into body-centered-cubic (bcc) structure, truncated rhombic dodecahedra enclosed with (110) and (100) are made. The shape-controlled assembly of binary nanocrystal supracrystals composed of plasmonic Au nanocrystals enables engineering the plasmonic near field coupling in binary nanocrystal supracrystals dispersed in water.

Although self-assembly across multiple length scales has been well recognized and intensively investigated in natural biological system, the design of artificial heterostructures enabled by integrative self-assembly is still in its infancy. Here we report a strategy toward the growth of discrete supracrystalline heterostructures from inorganic nanocrystals and porous organic cages (CC3- R), which in principle relies on the host–guest interactions between alkyl chains coated on nanocrystals and the cavity of cage molecules. Density functional theory calculation indicates that an attractive energy of ∼−2 k BT is present between an alkyl chain and the cavity of a CC3- R molecule, which is responsible for the assembly of nanocrystal superlattices on the CC3- R octahedral crystals. Of particular interest is that, determined by the shape of the nanocrystals, two distinct assembly modes can be controlled at the mesoscale level, which eventually produce either a core/shell or heterodimer supracrystalline structure. Our results highlight opportunities for the development of such a noncovalent integrative self-assembly not limited to a particular length scale and that could be generally applicable for flexible integration of supramolecular systems.