Volume 3: Innovative Solutions for Energy Transitions: Part II

Wettability of [Bmim] [Bf4] Ionic Liquid Droplet on Hydrophobic and Hydrophilic Substrates Fenhong Song, Bing Ma, Jing Fan, Gang Wang, Tieliu Jiang

Abstract

In this paper, molecular dynamics method was employed to investigate the wetting and electrowetting behaviors of nano-droplet of ionic liquid on a solid substrate with different wettability. The results show that the anion and cation groups are distributed in layers above the wall. The static contact angle decreases obviously when epsilon increases from 0.1 to 0.6 On the hydrophobic surface (ε=0.1), the droplet shows an asymmetric wetting when the imposed vertical electric field is in positive and negative direction. While on the hydrophilic surface (ε=3.0), the wetting of ILs droplet becomes nearly asymmetric because the strong solid attraction tend to dominate the wetting process. Through analyzing the distribution of coarse particles, it’s found that the asymmetric wetting is caused by the fact that the diffusion of cations on the substrate surface is stronger than that of anions.

Keywords electro-wetting, ILs droplet, asymmetric wetting, molecular simulation