Actuating Water Droplets on Graphene via Surface Wettability Gradients

作者：Liu Qingchang; Xu Baoxing^*

来源：Langmuir, 2015, 31(33): 9070-9075.

DOI：10.1021/acs.langmuir.5b02335

A surface wettability gradient can break the equilibrium status of a liquid droplet and drives its unidirectional movement on the surface. We propose a conceptual design of the driving water droplet on a graphene surface and demonstrate that both speed and direction of the movement can be controlled via a continuous gradient of surface wettability using comprehensive molecular dynamics (MD) simulations. Controlling the water droplet toward linear and nonlinear arc paths is exemplified in one- and two-dimensional gradients of surface wettability, respectively. Unbalanced Young's equation is extended to understand the speed of the droplet movement, and the predications agree well with MD simulations.

• 出版日期2015-8-25