Supracrystalline Colloidal Eggs: Epitaxial Growth and Freestanding Three-Dimensional Supracrystals in Nanoscaled Colloidosomes

Abstract

The concept of template-confined chemical reactions allows the synthesis of complex molecules that would hardly be producible through conventional method. This idea was developed to produce high quality nanocrystals more than 20 years ago. However, template-mediated assembly of colloidal nanocrystals is still at an elementary level, not only because of the limited templates suitable for colloidal assemblies, but also because of the poor control over the assembly of nanocrystals within a confined space. Here, we report the design of a new system called "supracrystalline colloidal eggs" formed by controlled assembly of nanocrystals into complex colloidal supracrystals through superlattice-matched epitaxial overgrowth along the existing colloidosomes. Then, with this concept, we extend the supracrystalline growth to lattice-mismatched binary nanocrystal superlattices, in order to reach anisotropic superlattice growths, yielding freestanding binary nanocrystal supracrystals that could not be produced previously.

Electron Tomography: A Unique Tool Solving Intricate Hollow Nanostructures

“…Extensive efforts have been devoted in the spatial localization, [155,156] long-/short-range ordering, [130,157] defect identification, [108,158] and precise compositional differentiation. Extensive efforts have been devoted in the spatial localization, [155,156] long-/short-range ordering, [130,157] defect identification, [108,158] and precise compositional differentiation.…”

“…Yang et al [108] report the assembly of Fe 3 O 4 nanocrystals inside a silica shell. Yang et al [108] report the assembly of Fe 3 O 4 nanocrystals inside a silica shell.…”

“…The yolk component can be a single particle, and also a collection of numerous nanocrystals. Yang et al [108] report the assembly of Fe 3 O 4 nanocrystals inside a silica shell. The complicated yolk-shell structure is beyond the capability of conventional TEM and HAADF-STEM analysis, especially the details on the nanocrystal spatial distributions and ordering (Figure 8a).…”

“…a-c) Reproduced with permission. [108] Copyright 2016, American Chemical Society. d-f) Reproduced with permission.…”

Nanoreactors: Small Spaces, Big Implications in Chemistry

“…Further, Pileni and co-workers revealed that the applicability of nanoreactors is not limited to chemical reactions between molecules. 19 In their system, nanocrystal growth into complex colloidal supracrystals was achieved through superlattice-matched epitaxial overgrowth along existing colloidosomal nanoreactors. Lastly, Palivan, Meier, and co-workers introduced another important type of nanoreactora polymer template in which binding sites are between 4.3 and 31.5 nm apart.…”