Electrowetting on a lotus leaf

Abstract

Electrowetting on dielectrics has been widely used to manipulate and control microliter or nanoliter liquids in micro-total-analysis systems and laboratory on a chip. We carried out experiments on electrowetting on a lotus leaf, which is quite different from the equipotential plate used in conventional electrowetting. This has not been reported in the past. The lotus leaf is superhydrophobic and a weak conductor, so the droplet can be easily actuated on it through electrical potential gradient. The capillary motion of the droplet was recorded by a high-speed camera. The droplet moved toward the counterelectrode to fulfill the actuation. The actuation speed could be of the order of 10 mm/s. The actuation time is of the order of 10 ms.

Contact angle hysteresis at the nanoscale: a molecular dynamics simulation study

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“…The resistive force resulting from CAH could be estimated by 2Rγ lv (cosθ r −cosθ a ) [21]. Balancing the two forces, we find that cosθ r −cosθ a can be written as:…”

Wetting Transition on Micro/Nanostructured ZnO Layers

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Observation of hydrophobic-like behavior in geometrically patterned hydrophilic microchannels

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