Morphogenesis of Magnetite Mesocrystals: Interplay Between Nanoparticle Morphology and Solvation Shell

Abstract

In this study, faceted mesocrystals have been assembled from the dispersion of truncated cubic-shaped iron oxide nanoparticles stabilized by oleic acid (OA) molecules using the non-solvent “gas phase diffusion technique” into an organic solvent. The effects of synthesis conditions as well as of the nanoparticle size and shape on the structure and morphogenesis of mesocrystals were examined. The interactions of OA capped iron oxide nanoparticles with solvent molecules were probed by analytical ultracentrifugation and double difference pair distribution function analysis. It was shown that the structure of the organic shell significantly depends on the nature and polarity of solvent molecules.

Self-Assembled Faceted Mesocrystals: Advances in Optimization of Growth Conditions

“…These experimental observations, however, cannot completely exclude the presence of homogeneous nucleation in solution but strongly support that formation of mesocrystals on the inclined solid substrate was initiated by heterogeneous nucleation. Recently, we also explored the effect of nanoparticles (including size, shape, solvation shell) and medium (type of solvent, i.e., its polarity) on the morphogenesis and structure of mesocrystals . The symmetry ( fcc , bct , or rhombohedral) of the superlattices strongly depends on the effective shape of the nanoparticles and the solvent polarity.…”

“…Recently, we also explored the effect of nanoparticles (including size, shape, solvation shell) and medium (type of solvent, i.e., its polarity) on the morphogenesis and structure of mesocrystals. 38 The symmetry (fcc, bct, or rhombohedral) of the superlattices strongly depends on the effective shape of the nanoparticles and the solvent polarity. Furthermore, the transition from bct to rhombohedral structure of mesocrystals grown on solid substrate could be "driven by a growth-induced in-plane compressive stress" 39 and depletion forces (due to the excess of surfactant -depletion agent).…”