Dissolvable smartwatch makes for easier electronics recycling

Small electronics, including smartwatches and fitness trackers, aren't easily dismantled and recycled. So when a new model comes out, most users send the old devices into hazardous waste streams. To simplify small electronics recycling, researchers have developed a two-metal nanocomposite for circuits that disintegrates when submerged in water. They demonstrated the circuits in a prototype transient device -- a functional smartwatch that dissolved within 40 hours.