Last week researchers showed off new nano generators that can produce electricity by harvesting energy from ultrasonic waves, mechanical vibrations and even blood flow.
The diminutive prototype generator could be used to power other nanodevices in the future, the researchers said, all without the need for batteries or other impractical or toxic external power sources.
"There has been a lot of interest in making nanodevices, but we have tended not to think about how to power them," said lead researcher Zhong Lin Wang in a statement last week.
"Our nanogenerator allows us to harvest or recycle energy from many sources to power these devices," Wang continued.
The generators use a series of vertically aligned zinc oxide nanowires that move inside a zigzag plate electrode. These nanowires each have unique semi conducting properties, according to Wang, and can produce small electrical charges when they are flexed by vibrations within the body or ultrasonic waves.
The zigzag electrode then serves as a Schottky barrier (a metal semiconductor junction) to the hundreds or thousands of nanowires and is able to harvest the energy they produce.