ApplicationCharacterizationCustomer publicationsMaterialNanoparticles & colloidsParticle interactionsParticle size and size distributionParticlesSAXSTechnique

Colloidal Solubility and Agglomeration of Apolar Nanoparticles in Different Solvents

Doblas, David; Kister, Thomas; Cano-Bonilla, Marina; González-García, Lola; Kraus, Tobias

Nano Letters, 2019, vol 19, 8, pp. 5246-5252

DOI:10.1021/acs.nanolett.9b01688

Abstract

We studied the concentration-dependent agglomeration of apolar nanoparticles in different solvents. Octanethiol-stabilized gold nanoparticles (AuNPs) in evaporating liquid droplets were observed in situ using small-angle X-ray scattering. Concurrent analysis of liquid volume and particle agglomeration provided time-dependent absolute concentrations of free and agglomerated particles. All dispersions underwent an initial stage where the particle concentration increased but no agglomerates formed. Subsequently, agglomeration started at concentrations that varied by several orders of magnitude for different solvents. While agglomerates grew, the concentration of the dispersed particles remained at a constant “colloidal solubility” in most solvents. We consistently found that the colloidal stability of AuNPs decreased as cyclohexane > heptane > nonane > decane > toluene and suggest that details of the molecular interactions between solvent and ligand shell set this order.

Visit the full article

Back to the overview