Abstract
A set of numerical models for two-dimensional self-assembly of nanoparticles in thin liquid films is developed and numerical simulations are carried out to investigate the relationship between process conditions and structures of self-assembled nanoparticles. The two-dimensional Langevin equation is employed to track nanoparticles on a substrate over time. Each nanoparticle is subject to multiscale surface forces such as capillary force, contact force, electrostatic force, van der Waals force and friction force, as well as Brownian force and fluid drag force. Three types of self-assembled structure, namely, crystal, non-isotropic aggregation and arrangement are obtained by twenty simulations. Three principles of two-dimensional self-assembly of nanoparticles in thin liquid films are proposed on the basis of the simulation results. The isotropic ordering factor and the non-dimensional boundary length are introduced to quantify the structures of self-assembled nanoparticles. Three types of self-assembled structure obtained here are specified according to sets of these criteria.
