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

  • Hwichul Yang
  • Hojae Lee
  • Yonghyun Lim
  • Maria Christy
  • Young-Beom KimEmail author
Regular Paper


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.


Energy harvesting Reverse electrowetting-on-dielectric Metal oxide thin films Leakage current Laminated structure 



This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(2012R1A6A1029029).


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Copyright information

© Korean Society for Precision Engineering 2019

Authors and Affiliations

  • Hwichul Yang
    • 1
  • Hojae Lee
    • 1
  • Yonghyun Lim
    • 1
  • Maria Christy
    • 1
  • Young-Beom Kim
    • 1
    • 2
    Email author
  1. 1.Department of Mechanical Convergence EngineeringHanyang UniversitySeoulRepublic of Korea
  2. 2.Institute of Nano Science and TechnologyHanyang UniversitySeoulRepublic of Korea

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