Researchers at NC State UniversitY have demonstrated new wearable technologies that both generate electricity from human movement and improve the comfort of the technology for the people wearing them.

The materials incorporate molecules called amphiphiles, which are often used in consumer products such as diapers to reduce friction against human skin. The research team first developed a model to provide a fundamental understanding of how different amphiphiles affect the surface friction of different materials. Then, they started a series of experiments to see if they could incorporate amphiphiles into haptic energy harvesters.

The researchers found that some amphiphiles have electronic properties that allow them to “donate” electrons. And when these electron-donating amphiphiles were incorporated into the wearable materials, the end result was a material that was both comfortable and capable of generating electricity through friction produced by rubbing against human skin or other materials.

“The technology for harvesting static energy is well established, but devices that can be worn for long periods of time are still missing,” said Lilian Hsiao, associate professor of chemical and biomolecular engineering. “In our proof-of-concept testing, we found these amphiphile materials not only feel good on the skin but could generate up to 300 volts, which is remarkable for a small piece of material.”

“We’re interested in doing more to make use of these materials, such as exploring how they can be incorporated into existing haptic devices,” said Saad Khan, INVISTA Professor of Chemical and Biomolecular Engineering. “And we’re open to working with industry partners on identifying new applications.”