Effects of stripy surfaces with intervals on the coalescence dynamics of nano-droplets: Insights from molecular dynamics simulations

Molecular dynamics (MD) simulations are employed to study the coalescence behaviors of nano-droplets on the stripy substrates decorated with spaced graphene nanoribbons (GNRs) for the first time. Results show that the stripe-induced restriction effect causes great inhibition to the coalescence dynamics, in which the downward movement of the droplet resulting from the penetration of atoms plays a predominant role. And the larger the intervals are, the heavier the restriction effect becomes. Additionally, it is found that the diffusion direction of the droplet during the coalescence process can be altered under different width of the stripe. Furthermore, when the direction of stripes is placed in accordance with that of the coalescence, the coalescence process would be faster. More importantly, based on our studies, the stripy surfaces with gradient intervals are well designed, where the coalescence behaviors could be finely manipulated. This work may open up a new way to control the coalescence dynamics by designing the stripy surface, which can provide guidance for some potential applications, such as micro-coating, micro-fabricated devices and even 3D printing.