Developing a wearable, skin-based triboelectric nanogenerator

Abstract

The widespread adoption of alternative energy sources is increasingly important as we try to create a more sustainable future. The wearable electronics field is growing at a rapid rate. In addition to smart devices like smartwatches and fitness trackers, biosensors are becoming progressively more popular to track critical health data. Summer temperatures in Texas regularly rise over 100°F, often coinciding with summer activities and camps. Left unchecked, this can lead to serious consequences, including heatstroke. A triboelectric nanogenerator (TENG) embedded in one’s shirt can be used to sustainably power a temperature sensor to prevent heat emergencies. We hypothesized that the triboelectricity generated from the friction between one’s skin and a negatively charged material placed on the inside of a shirt would produce enough voltage to power these biosensors. We tested numerous negatively charged materials and conductors to determine the optimal design of the generator. Our results revealed that silicone was the superior negatively charged material, producing nearly twice as much voltage as Teflon and five times more than cellophane. We tested the conductors and found that copper produced over 50% more voltage than aluminum. The wearable triboelectric nanogenerator (W-TENG) utilized silicone and copper, the superior negatively charged material and conductor, respectively. The W-TENG produced an average of 3.6 volts while running, enough to power the temperature sensor. Our project is novel due to its usage of skin as the positively charged material in a hybrid contact-separation/sliding mode TENG. The W-TENG created and tested in this experiment shows promise for tracking body temperature and preventing impending heat emergencies.