Diffusion of a liquid nanoparticle on a disordered substrate

TL;DR

This study uses molecular dynamics simulations to analyze how liquid nanoparticles diffuse on disordered surfaces, revealing a normal diffusion process despite prolonged sticking periods and proposing a model linking diffusion to size and temperature.

Contribution

It introduces a phenomenological model describing the size and temperature dependence of nanoparticle diffusion, highlighting the scaling of activation energy with particle size.

Findings

Nanoparticles exhibit normal diffusion despite long sticking times.

Diffusion coefficient depends on size and temperature, with activation energy scaling as N^{1/3}.

Simulation results support the proposed phenomenological model.

Abstract

We perform molecular dynamic simulations of liquid nanoparticles deposited on a disordered substrate. The motion of the nanoparticle is characterised by a 'stick and roll' diffusive process. Long simulation times ($\simeq \mu s$), analysis of mean square displacements and stacking time distribution functions demonstrate that the nanoparticle undergoes a normal diffusion in spite of long sticking times. We propose a phenomenological model for the size and temperature dependence of the diffusion coefficient in which the activation energy scales as $N^{1/3}$.