Experimental Analysis of Rotary Freestanding Triboelectric Nanogenerators

In this paper, we design, develop, and test rotary freestanding triboelectric nanogenerators (TENGs) for harvesting energy from mechanical rotation. The objective is characterizing the fundamental processes involved in energy harvesting and obtaining a thorough understanding of the development process for TENG devices. An experimental testbed was built for mounting, testing, and analyzing the TENG electrical characteristics. To test the electrical performance, several versions of TENGs were created with varying design and measurement parameters. We measured the effects of changing the diameter (50, 75, 100mm) and changing the number of blades (4, 8 and 12-blade). We also analyzed the effect of changing RPM, applied torque and electrode materials on the output performance produced. Additionally, we also measured and characterized the performance of thin-film MEMS deposition techniques by depositing an Aluminum Oxide (Al2O3) layer and Aluminum (Al) electrode layer for the TENGs. The 12-blade 100mm TENG produced an open circuit voltage of 180VOC and a short circuit current of 10μA at 1000RPM and 0.04Nm applied torque. The Al2O3 thin-film blocking layer exhibited a two-fold increase in current and a three-fold increase in voltage output for the tested TENG devices.