Impact of Rough Surface Morphology of Diluted Poly-DiMethyl-Siloxane (PDMS) Polymer Film on Triboelectric Energy Harvester Performance

Abstract

In this paper, impact of rough surface formed of diluted Poly-DiMethyl-Siloxane (PDMS) polymer film as one of the tribo layer, on performance of Triboelectric Energy Harvester (TEH) device is demonstrated. A parallel plate vertical-separation mode type TEH is fabricated in which tribo-pair, metal-dielectric is implemented utilizing copper as metal and PDMS polymer with altered surface morphology, as a dielectric film. FR4 substrate with single side copper clad is used to realize bottom electrode, on which dielectric tribo layer is implemented with diluted PDMS formed by mixing 25wt% water in Dow Corning 10:1 PDMS solution to attain the increased surface roughness. Top electrode is a cantilever structure implemented utilising $50 \mu$m thin copper foil. Mechanical energy in the form of vibrations is provided on the top of cantilever structure. The device measurements are carried out using DSO (digital oscilloscope), which showed the peak output voltage of 33.6V. As proof of concept, device is demonstrated in a system by connecting to 26 serially connected LEDs (light emitting diodes) and all LEDs were glowing on providing the vibrational energy with manual tapping on the TEH device.