Mesocrystals: Inorganic Superstructures Made by Highly Parallel Crystallization and Controlled Alignment

Abstract

Controlled self-organization of nanoparticles can lead to new materials. The colloidal crystallization of non-spherical nanocrystals is a reaction channel in many crystallization reactions. With additives, self-organization can be stopped at an intermediary step-a mesocrystal-in which the primary units can still be identified. Mesocrystals were observed for various systems as kinetically metastable species or as intermediates in a crystallization reaction leading to single crystals with typical defects and inclusions. The control forces and mechanism of mesocrystal formation are largely unknown, but several mesocrystal properties are known. Mesocrystals are exiting examples of nonclassical crystallization, which does not proceed through ion-by-ion attachment, but by a modular nanobuilding-block route. This path makes crystallization more independent of ion products or molecular solubility, it occurs without pH or osmotic pressure changes, and opens new strategies for crystal morphogenesis.

Biomimetic and Aggregation-Driven Crystallization Route for Room-Temperature Material Synthesis: Growth of β-Ga2O3 Nanoparticles on Peptide Assemblies as Nanoreactors

“…The term, aggregation-driven crystallization, is defined as a process in which a single crystal is grown by the aggregation in an aligned manner and the fusion of primary nanoparticles. 5 The peptide assembly used in this study captured the nucleated primary particles, mineralized them to β-Ga 2 O 3 crystals using its catalytic functions, and then fused them to grow single-crystalline and monodisperse nanoparticles in the cavity of the peptide assembly at room temperature.…”

Fabrication of EuF3‐Mesocrystals in a Gel Matrix

“…In addition, polarisation microscopy with crossed polarisers shows a strong, very homogeneous birefringence with uniform colour over distances > 100 µm, which is a proof for the iso-orientation of the nanoparticle aggregates even on the micron scale. Therefore, the obtained nanoparticle superstructure is a mesocrystal [1], [2], [19] .…”

“…Recently, non classical crystallization was found to be a tool for controlled nanoparticle organization to superstructures or single crystals, thus generating so-called mesocrystals, superstructures built up by nanocrystals which are in mutual alignment [1][2][3] . Often the crystalline building blocks are in perfect three-dimensional crystalline registry.…”

Self-organization of hollow-cone carbonate crystals through molecular control with an acid organic polymer

“…[15][16][17] These mesocrystal structures have attracted considerable interest in recent years. [18][19][20] Learning from biomineralization, mesocrystal structures have been synthesized with synthetic organic molecules. Biomimetic morphological control of crystals has been studied in a variety of inorganic materials using organic molecules.…”

“…Based on previous reports, [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] organic molecules have three main roles in crystallization processes: templates for crystallization, additives for growth control through the interaction at crystal faces and agents for diffusion control. Organic macromolecules serve as templates for crystal growth through heterogeneous nucleation (Effect I).…”