This paper reports an open-loop method for highly efficient and precise droplet manipulation with
polarity-dependent low-voltage electrowetting on a perfluorinated silane modified slippery liquid infused
porous surface (SLIPS) in which a droplet can be driven between individual square electrodes. The
electrowetting phenomenon on modified SLIPS was investigated first, and it exhibited an up to 551
contact angle difference with respect to voltage polarity while the threshold voltage was reduced to
only 2 V. Then, a coplanar electrode experiment was designed to study the performance of droplet
manipulation on several modified SLIPS samples with different vertically placed times and silicon oil
viscosities. The optimal condition for preparing a modified SLIPS membrane is that a sample is placed
vertically for 2 hours after infusing 10 cSt silicon oil, on which the droplet can be driven with the fastest
velocity, and the activation voltage for moving a droplet is only 8 V. Finally, multi-droplet simultaneous
and continuous manipulation on modified SLIPS in bi-direction on a loop of square electrodes was
achieved. Interestingly, unlike asymmetric electrowetting, actuation methods on a solid insulator and
hydrophobic layers, the droplet actuation velocity was not limited by the contact angle saturation effect
and always increased with the applied voltage on modified SLIPS. This method achieves a very wide
range of droplet continuous manipulation velocities from 0.075 mm s 1 to 123 mm s 1 under 20 V to
500 V applied voltage and the continuous droplet actuation voltage exhibits at least a 15-fold decrease
compared to that of an unmodified SLIPS membrane.