Details

Autor(en) / Beteiligte

• Wetterskog, Erik
• Klapper, Alice
• Disch, Sabrina
• Josten, Elisabeth
• Hermann, Raphaël P
• Rücker, Ulrich
• Brückel, Thomas
• Bergström, Lennart
• Salazar-Alvarez, German

Titel

Tuning the structure and habit of iron oxide mesocrystalsElectronic supplementary information (ESI) available: Morphological characterization of the nanocubes, further GISAXS analysis and indexed patterns, AFM images, additional SEM images, mesocrystal surface reconstruction using SEM images, and magnetic characterization. See DOI: 10.1039/c6nr03776c

Erscheinungsjahr

2016-08

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• A precise control over the meso- and microstructure of ordered and aligned nanoparticle assemblies, i.e. , mesocrystals, is essential in the quest for exploiting the collective material properties for potential applications. In this work, we produced evaporation-induced self-assembled mesocrystals with different mesostructures and crystal habits based on iron oxide nanocubes by varying the nanocube size and shape and by applying magnetic fields. A full 3D characterization of the mesocrystals was performed using image analysis, high-resolution scanning electron microscopy and Grazing Incidence Small Angle X-ray Scattering (GISAXS). This enabled the structural determination of e.g. multi-domain mesocrystals with complex crystal habits and the quantification of interparticle distances with sub-nm precision. Mesocrystals of small nanocubes ( l = 8.6-12.6 nm) are isostructural with a body centred tetragonal ( bct ) lattice whereas assemblies of the largest nanocubes in this study ( l = 13.6 nm) additionally form a simple cubic ( sc ) lattice. The mesocrystal habit can be tuned from a square, hexagonal to star-like and pillar shapes depending on the particle size and shape and the strength of the applied magnetic field. Finally, we outline a qualitative phase diagram of the evaporation-induced self-assembled superparamagnetic iron oxide nanocube mesocrystals based on nanocube edge length and magnetic field strength. A precise control over the meso- and microstructure of ordered and aligned nanoparticle assemblies, i.e. , mesocrystals, is essential in the quest for exploiting the collective material properties for potential applications.