Observation of contact angle hysteresis due to inhomogeneous electric fields

Abstract Static contact angle hysteresis determines droplet stickiness on surfaces, and is widely attributed to surface roughness chemical contamination. In the latter case, defects create free-energy barriers that prevent line motion. Electrowetting studies have demonstrated similar ability of electric fields alter landscape. Yet, increase apparent static by remains unseen. Here, we report observation electrowetting micro-striped electrodes. Unlike most experiments with stripes, spreading substrate experimentally found be isotropic, which allows deriving a simple theoretical model depending applied voltage. This enables continuous dynamic control hysteresis, not only for fundamental but also manufacture sticky-on-demand surfaces sample collection.