Wetting behaviour of a translating sessile nanodrop under electrostatic actuation

Abstract

Molecular dynamics (MD) simulation is performed to investigate the wetting characteristics of a nanosized pure water droplet subjected to a differential electric field. The drop considered is placed on strips of silicon electrode which can be charged and switched progressively in a direction. The results of the switching electrodes show that the droplet translates over the substrate and its dynamics can be controlled by tuning the electrode actuation. The wetting phenomenon during translation shows two distinct stages in which a precursor film forms first which subsequently drags the bulk liquid with the help of progressive switching. The frequency of the shifting charged region below the drop and magnitude of the assigned charge both have a significant impact on the translation and can be optimized for desired translation parameters. Controlled mobility of the nanodrops of a polar liquid using an electric field is perfectly aligned with the rapid technological development in nano-mission and may open up applications in the areas of biomedical and applied chemistry research.