A team of South Korean scientists from Hanyang University recently collaborated with scientists from the University of Texas to develop high-tech yarn that generates electricity. The newly developed “twistron” yarns made from carbon nanotubes can harvest energy when stretched or twisted. First, the yarns are submerged in electrolytes to charge them without external voltage. After twisting the yarn and reducing the volume of carbon nanotubes, the researchers brought electric charges closer together and the energy of the yarn increased. With 30 stretches per second, 250 watts per kg of peak electrical power can be harvested.
This novel approach to generating electricity raises questions on its seemingly endless applications. Twistrons may power sensors for the Internet of Things, since switching batteries can be impractical. For example, when a twistron is sewn into a shirt, breathing stretches the yarn and enables generation of electricity so that it can act as a self-powered respiration sensor. Another potential lies in installing the yarn in the sea — utilizing seawater as the electrolyte and waves as the motion to stretch the twistron. More can be found about twistrons in the latest issue of Science.