Humans have long envied fish their ability to breathe underwater. A few extreme athletes trained in the sport of freediving—in which divers swim underwater or perform aquatic feats on a single breath—have been able to hold their breath for more than 20 minutes. (The current world record is held by Croatian free diver Budimir Šobat, who held his breath while staying underwater for 24 minutes, 11 seconds in February 2018.) But that’s not breathing underwater.
So envious are we, in fact, that it shouldn't surprise us that there have been songs written about this elusive phenomenon.
Researchers have created energy-harvesting yarn from tightly coiled carbon nanotubes, which can be activated by the electrolytes in a simple saline solution. With no need for a battery, these “twistron yarns” have numerous potential applications in wearable, medicinal and oceanic contexts.
How twistron yarn is made
An international research team led by scientists at The University of Texas at Dallas (UT Dallas) and Hanyang University in South Korea constructed the yarn from carbon nanotubes—hollow cylinders 10,000 times smaller in diameter than a human hair. After twist-spinning sheets of carbon nanotubes—with a motion similar to a spinning wheel—to create strong, lightweight yarns, researchers introduced elasticity with additional twist until the yarns coiled akin to an over-twisted rubber band.