Advancement of Reverse Electrowetting-on-Dielectric With Flexible Electrodes for Bias-Free Energy- Harvesting Applications

Energy harvesting with the utilization of the reverse electrowetting-on-dielectric (REWOD) phenomenon is a unique method of generating energy by implementing electrolyte impingement using mechanical modulation. The goal of wearable motion sensors that are self-powered has been undermined by the prior REWOD research’s emphasis on planar electrodes, which are not flexible and require high-voltage bias to improve output power. In this article, REWOD-based energy harvesting is implemented using two sets of dissimilar flexible electrodes. The electron-beam physical vapor deposition (EBPVD) technique is utilized to coat materials on polyimide sheet. In the first planar REWOD experiment, mechanical energy was harvested through electrolyte impingement via 2-mm electrode displacement between the top and bottom electrodes. In a second REWOD experiment, the electrodes underwent a flexing test with electrolyte encapsulated between the electrodes. The planar experiment resulted in the maximum power density value of
$0.002 \mu \text{W}$
/cm2, and the proposed flexing REWOD test measurement with electrolyte encapsulated between both electrodes resulted in
$0.05 \mu \text{W}$
/cm2 of power density, which is
$\approx 25$
times higher than the value generated using the conventional REWOD setup.