Shape Induced Symmetry in Self-Assembled Mesocrystals of Iron Oxide Nanocubes

Jülich Centre for Neutron Science JCNS and Peter Grünberg Institut PGI, JARA-FIT, Forschungszentrum Jülich, 52425 Jülich, Germany.
Nano Letters (Impact Factor: 13.59). 03/2011; 11(4):1651-6. DOI: 10.1021/nl200126v
Source: PubMed


Grazing incidence small-angle scattering and electron microscopy have been used to show for the first time that nonspherical nanoparticles can assemble into highly ordered body-centered tetragonal mesocrystals. Energy models accounting for the directionality and magnitude of the van der Waals and dipolar interactions as a function of the degree of truncation of the nanocubes illustrated the importance of the directional dipolar forces for the formation of the initial nanocube clusters and the dominance of the van der Waals multibody interactions in the dense packed arrays.

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Available from: Sabrina Disch, Oct 02, 2015
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    • "Growth of iron oxide mesocrystals shares many aspects with classical crystal growth. The mesocrystals composed of 9.6 nm nanocubes shown in figure 6(b) are cuboidal as a result of their body-centered tetragonal (bct) mesostructure [44] [46]. It is also in some cases possible to observe step edges on the flat top surfaces of the mesocrystals (see figure 6(c)). "
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    Advanced Powder Technology 02/2014; 25(5). DOI:10.1016/j.apt.2014.02.006 · 2.64 Impact Factor
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    • "It should be noted that the formation of ordered 3D nanoparticle arrays by the spontaneous solvent evaporation has been well explored and documented for noble metal nanoparticles [6] [7] [8]. Adopting a multilayer concept of the 3D nanoparticle array we will demonstrate that using GISAXS with the appropriate simulation toolkit it is possible to distinguish between a nanoparticle multilayer with laterally (along the substrate) ordered but vertically disordered layers in terms of the nanoparticle positions and a fully ordered 3D nanoparticle array with both lateral and vertical ordering. "
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