Laminated Structure of Al2O3 and TiO2 for Enhancing Performance of Reverse Electrowetting-On-Dielectric Energy Harvesting

Reverse electrowetting-on-dielectric (REWOD) is a novel energy harvesting technique that has been gaining considerable amount of attention owing to its high power output even with the small amount of disturbance. To enhance the output power of REWOD, the dielectric layers in the system require a high capacitance. Nevertheless, current leakage is inevitable in such high-k dielectric materials. In this work, the application of a high-k dielectric material TiO2 has been investigated along with a new leakage barrier layer Al2O3 that acts as a lamination, in order to minimize the current leakage and maximize the power output. As expected, the laminated structure with TiO2 and Al2O3 exhibited reduced current leakage and relatively high capacitance compared to the single layer of TiO2 or Al2O3, respectively. As the electrical energy is generated through the interaction of liquid droplets and the multilayered dielectric film, the energy-harvesting performance displayed different behavior about current generation with respect to the top surface material that is in contact with the conductive droplet. Overall, the laminated REWOD energy harvesting system produced an enhanced power density of 15.36 mW cm(-2) at a low bias voltage.

Automated summary

Reverse electrowetting-on-dielectric (REWOD) is a novel energy harvesting technique that uses high capacitance dielectric layers and a new leakage barrier layer to minimize current leakage and maximize power output. The laminated structure with TiO2 and Al2O3 shows reduced current leakage and relatively high capacitance compared to single layer structures, producing enhanced power density at low bias voltage. The energy-harvesting performance displays different behaviors about current generation based on the top surface material in contact with conductive droplets.