"Air humidity is a vast, sustainable reservoir of energy that, unlike solar and wind, is continuously available," said the study, which was published recently in the journal Advanced Materials.
“This is very exciting,” said Xiaomeng Liu, a graduate student at the University of Massachusetts-Amherst, and the paper’s lead author. “We are opening up a wide door for harvesting clean electricity from thin air.”
In fact, researchers say, nearly any material can be turned into a device that continuously harvests electricity from humidity in the air.
“The air contains an enormous amount of electricity,” said Jun Yao, assistant professor of electrical and computer engineering at the University of Massachusetts-Amherst and the paper’s senior author. “Think of a cloud, which is nothing more than a mass of water droplets. Each of those droplets contains a charge, and when conditions are right, the cloud can produce a lightning bolt – but we don’t know how to reliably capture electricity from lightning.
"What we’ve done is to create a human-built, small-scale cloud that produces electricity for us predictably and continuously so that we can harvest it.”
The heart of the human-made cloud depends on what Yao and his colleagues refer to as an air-powered generator, or the "air-gen" effect.
The study builds on research from a study published in 2020. That year, scientists said this new technology "could have significant implications for the future of renewable energy, climate change and in the future of medicine." That study indicated that energy was able to be pulled from humidity by material that came from bacteria; the new study finds that almost any material, such as silicon or wood, also could be used.
The device mentioned in the study is the size of a fingernail and thinner than a single hair. It is dotted with tiny holes known as nanopores, it was reported. "The holes have a diameter smaller than 100 nanometers, or less than a thousandth of the width of a strand of human hair."