Nanotechnology that captures energy from human motion

You may soon be able to charge cell phones and power Bluetooth headsets with the swipe of a finger as scientists have developed a device that can harvest energy from human motion.

According to a research published in the journal "Nano Energy", a foldable keyboard called "Biocompatible Ferroelectret Nanogenerator" (FENG) that operates by touch and for which no battery is needed can harvest energy from human motion.

"We are on the path toward wearable devices powered by human motion," said Nelson Sepulveda, Associate Professor at Michigan State University. He added, "What I foresee, relatively soon, is the capability of not having to charge your cell phone for an entire week, for example, because that energy will be produced by your movement."

The scientists used the low-cost device to successfully operate an LCD touch screen, a bank of 20 LED lights and a flexible keyboard, all with a simple touching or press motion and without the aid of a battery.

According to the scientists, the process starts with a silicone wafer, which is then fabricated with several layers of environmentally friendly substances including silver, polyimide and polypropylene ferroelectret.

"Ions are added so that each layer in the device contains charged particles. Electrical energy is created when the device is compressed by human motion, or mechanical energy," the study explained.

FENG is as thin as a sheet of paper and can be adapted to many applications and sizes.

"Advantages such as being lightweight, flexible, biocompatible, scalable, low-cost and robust could make FENG an alternative method in the field of mechanical-energy harvesting for many autonomous electronics such as wireless headsets, cell phones and other touch-screen devices," the study suggested.

When FENG is folded, the amount of voltage a person creates is exponentially increased in it.

"You can start with a large device, but when you fold it once, and again, and again, it is now much smaller and has more energy," said Sepulveda.

--IANS

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