Kinetics and morphology of cluster growth in a model of short-range attractive colloids

Khan, Siddique J.; Sorensen, C. M.

doi:10.1063/1.3262311

Cited by 13 publications

(14 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, we note that while it has been previously shown 31 that the van der Waals interaction can play a significant role in the binding of NPs to form islands, the results presented here indicate that the van der Waals interaction also has a significant effect on the binding energy and position of individual Au NPs at the solventvapor interface. Accordingly, we believe that in future simulations of NP adsorption this effect should be explicitly included.…”

Section: Discussionsupporting

confidence: 46%

Adsorption and diffusion of colloidal Au nanoparticles at a liquid-vapor interface

Poddar

Amar

2014

The Journal of Chemical Physics

View full text Add to dashboard Cite

Motivated by recent drop-drying experiments of Au nanoparticle (NP) island self-assembly, we investigate the structure, diffusion, and binding of dodecanethiol-coated Au NPs adsorbed at the toluene-vapor interface using molecular dynamics (MD) simulations as well as analytical calculations. For a 6 nm core diameter NP our results indicate the existence of significant intermixing between the ligands and the solvent. As a result, the NP lies primarily below the interface with only a portion of the ligands sticking out, while the toluene-vapor interface is significantly higher in the region above the NP core than away from the NP. These results are consistent with a competition between the negative free energy of mixing of toluene and the dodecanethiol ligands, which tends to keep the NP below the interface, and the effects of surface tension which keeps the NP near the interface. Consistent with this result, we find that the coefficient for nanoparticle diffusion along the interface is close to the Stokes-Einstein prediction for three-dimensional bulk diffusion. An analysis of the ligand arrangement surrounding the NP also indicates that there is relatively little asymmetry in the ligand-coating. We then consider the effects of van der Waals interactions on the adsorption energy. In particular, we derive an analytical expression for the van der Waals interaction energy between a coated nanoparticle and the surrounding solvent along with a closed-form expression for the van der Waals corrections to the binding energy at the interface due to the long-range core-solvent interaction. Using these results along with the results of our MD simulations, we then estimate the van der Waals corrections to the adsorption energy for dodecanethiol-coated Au nanoparticles at the toluene-vapor interface as well as for decanethiol-coated nanoparticles at the water-vapor interface. In both cases, we find that the long-range core-solvent interaction may significantly reduce the binding energy. Based on these results, we conclude that in many cases, the core-solvent van der Waals interaction is likely to have a significant effect on the binding energy and interface position of Au NPs. Our results also indicate that the competition between the van der Waals interaction and the short-range attraction to the interface leads to the existence of well-defined activation barriers for nanoparticle adsorption from the solvent as well as for interfacial desorption.

show abstract

Section: Discussionsupporting

confidence: 46%

Adsorption and diffusion of colloidal Au nanoparticles at a liquid-vapor interface

Poddar

Amar

2014

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…The data are well-t by the function at 1/D , where a value of 1/D ¼ 0.35 was extracted from a non-linear least-squares method. In this case D, the effective fractal dimension, 29 is consistent with a dimensionality of 3, that is, a compact, dense spheroid. It is apparent that aggregation is much more rapid than observed following a 16% ethanol shock.…”

Section: Resultsmentioning

confidence: 64%

Ethanol shock and lysozyme aggregation

et al. 2013

View full text Add to dashboard Cite

“…4. The number of clusters decreases inversely with time (i.e., the kinetic exponent z ¼ 1) and the radius of gyration increases as a power law with an exponent of n ¼ 0.5 (21,22). The relation between z and n involves the fractal dimension in the following way: n ¼ z/D f .…”

Section: Resultsmentioning

confidence: 99%

Kinetics of Nanochain Formation in a Simplified Model of Amelogenin Biomacromolecules

Liu

Pérez

et al. 2011

Biophysical Journal

Self Cite

View full text Add to dashboard Cite

We show that the kinetics of nanochain formation of amelogenin molecules is well described by a combination of translational and rotational diffusion of a simplified anisotropic bipolar model consisting of hydrophobic spherical colloid particles and a point charge located on each particle surface. The colloid particles interact via a standard depletion attraction whereas the point charges interact through a screened Coulomb repulsion. We study the kinetics via a Brownian dynamics simulation of both translational and rotational motions and show that the anisotropy brought in by the charge dramatically affects the kinetic pathway of cluster formation and our simple model captures the main features of the experimental observations.

show abstract

Kinetics and morphology of cluster growth in a model of short-range attractive colloids

Cited by 13 publications

References 57 publications

Adsorption and diffusion of colloidal Au nanoparticles at a liquid-vapor interface

Adsorption and diffusion of colloidal Au nanoparticles at a liquid-vapor interface

Ethanol shock and lysozyme aggregation

Kinetics of Nanochain Formation in a Simplified Model of Amelogenin Biomacromolecules

Contact Info

Product

Resources

About