Bio-inspired semi-infused adaptive surface with reconfigurable topography for on-demand droplet manipulation

Abstract

On-demand manipulation of droplets on surfaces plays an important role for many applications but the fabrication of a platform capable of efficient stimuli-free pinning on any tilted surfaces without any external forces and precise motion of droplets at different states is still challenging. Herein we report a novel magnetoresponsive semi-infused adaptive surface for droplet manipulations. The responsive surface is made by semi-infusing a magnetic-responsive lubricant into a porous substrate. The topography of the surface can be reversibly switched between semi-infused and oil-accumulated states by the availability of an external magnetic field. The switching can turn droplets from a Cassiel state to a Wenzel state and the systems allow for stimuli-free pinning of droplets in a tilted state and on-demand motion of liquid droplets. This platform may have potential in the design of smart material interfaces, microfluidic devices, and chemical reactors.