Triboelectricity, can often produce static electricity, and is a phenomenon that was first recorded some 2500 years ago by the Greek philosopher Thales of Miletus. Upon rubbing a piece of amber with fur, Thales noted that the amber was able to pick up pieces of straw and dust from a distance. Many centuries later, William Gilbert coined the term “electra” and electricity, derived from the Greek word for amber, elektron. The prefix “tribo” means rubbing in Greek, so triboelectricity means electricity resulting from rubbing. Most of the static electricity that we observe in our daily lives is triboelectricity in action.
The mechanism of triboelectricity is not entirely understood. It is currently thought to be similar to adhesion, which is also not fully understood. Importantly, despite “tribo” meaning rubbing or friction, two materials must simply come into contact in order for charges to be transferred from one material to another.
Materials vary in their affinity for obtaining electrical charges. As of this writing, only broad generalizations can be made regarding what affinity for charges different materials have. Typically, materials are listed relative to one another in what is called the triboelectric series. A scientific instrument that can be used to create a triboelectric series is called an electroscope. Instructions for building a low-cost electroscope can be found in the links to the right.
Scientists and engineers take advantage of triboelectricity as a method of converting kinetic energy into electrical energy. These devices, called triboelectric nanogenerators (TENGs), vary in their designs and applications. In the links to the right you will find instructions for building a low-cost triboelectric nanogenerator developed by the Wisconsin MRSEC. Applications for TENGs range from large-scale energy production (e.g. networks of TENGs suspended in the ocean) to battery-less portable electronics (e.g. smart watches) to wound healing.
References
- Zou, H., Zhang, Y., Guo, L., Wang, P., He, X., Dai, G., Zheng, H., Chen, C., Wang, A. C., Xu, C., and Wang, Z. L. (2019). “Quantifying the triboelectric series.” Nature Communications, 10(1), 1427.
- Lacks, D. J., Sankaran, R. M. (2019).
“Shining Light on Triboelectric Phenomena.” Matter, 1(3), 552-553. - Lacks, D. J., Shinbrot, T. (2019). “Long-standing and unresolved issues in triboelectric charging.” Nature Reviews Chemistry, 3, 465–476.