Growth modes of nanoparticle superlattice thin films

TL;DR

This paper investigates how solvent and substrate interactions influence the growth modes of iron oxide nanoparticle superlattice thin films, revealing mechanisms behind layerwise and mesocrystalline growth for advanced material design.

Contribution

It provides new insights into controlling nanoparticle film morphology through solvent and substrate interactions during self-assembly.

Findings

Wetting vs. dewetting influences film morphology

Identification of layerwise and mesocrystalline growth modes

Understanding of self-assembly mechanisms

Abstract

We report about the fabrication and characterization of iron oxide nanoparticle thin film superlattices. The formation into different film morphologies is controlled by tuning the particle plus solvent-to-substrate interaction. It turns out that the wetting vs. dewetting properties of the solvent before the self-assembly process during solvent evaporation plays a major role to determine the resulting film morphology. In addition to layerwise growth also three-dimensional mesocrystalline growth is evidenced. The understanding of the mechanisms ruling nanoparticle self-assembly represents an important step toward the fabrication of novel materials with tailored optical, magnetic or electrical transport properties.