Highly efficient superhydrophobic surface-based triboelectricnanogenerator for rotational machineries

In this paper, we propose super-hydrophobic surface-based triboelectric nanogenerators (TENGs) which can be employed to harvest mechanical energy from rotational machineries to power battery-less sensor nodes. The proposed TENGs consist of a coaxial cylindrical structure connected with a motor and two Al electrode covered by various PDMS films. Surface-structured PDMS thin films induce more charges on the surface due to the increase of contact area. The PDMS thin film with pyramid structures on the surface shows the highest output performance in comparing with others. However, among three different surface structures, dual-scaled PDMS film made by an under-baked and under-exposed PR mold shows a better hydrophobicity compared to pyramid and artificial lotus leaf PDMS structures. Self-cleaning effect is also demonstrated with the proposed TENG system. We believe that the proposed TENG has a great potential to realize battery-less sensor systems.