
Energy-harvesting design aims to turn Wi-Fi signals into usable power - gigama
https://news.mit.edu/2020/energy-harvesting-wi-fi-power-0327
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gigama
TL;DR...

"Any device that sends out a Wi-Fi signal also emits terahertz waves —
electromagnetic waves with a frequency somewhere between microwaves and
infrared light. These high-frequency radiation waves, known as 'T-rays,' are
also produced by almost anything that registers a temperature, including our
own bodies and the inanimate objects around us."

"They found that in this [honeycomb] arrangement, the forces between
graphene’s electrons were knocked out of balance: Electrons closer to boron
felt a certain force while electrons closer to nitrogen experienced a
different pull. The overall effect was what physicists call 'skew scattering,'
in which clouds of electrons skew their motion in one direction."

"...a terahertz rectifier that consists of a small square of graphene that
sits atop a layer of boron nitride and is sandwiched within an antenna that
would collect and concentrate ambient terahertz radiation, boosting its signal
enough to convert it into a DC current."

“This would work very much like a solar cell, except for a different frequency
range, to passively collect and convert ambient energy,” Fu says.

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zapttt
in other news: let's put a turbine on an open faucet!

