Since the concept of nanosystems first arose, people have asked “how will these things be powered?” Now there’s another answer from Z.L. Wang at Georgia Tech, in a paper published April 6 in Science. Extremetech explains:

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.

With further optimization, Wang says that he and his group expect their nanogenerators could produce as much as four watts per cubic centimeter, more than enough to power a variety of environmental, biomedical, and defense-based nano-scale devices…

Wang also notes that these generators could be used to power much more than nanodevices.

“If you had a device like this in your shoes when you walked, you would be able to generate your own small current to power small electronics,” Wang said. “Anything that makes the nanowires move within the generator can be used for generating power. Very little force is required to move them.”

Science’s editors explain further:

Because different wires are actuated at different times, a continuous electrical current is generated.

So, both the nanodevices and macrodevices in our future wearables may be powered by our own walking. Maybe this will get people walking more. (Probably not. They could instead use the movement of our breathing. Or our fingers pressing the remote control, or arms reaching for a bag of chips.)

Anyone see a reason that this principle couldn’t work at the molecular scale? Don’t assume a water environment. (Credit —Christine