|Researchers have accidentally created nanorods that can absorb water at low humidity and expel it as the humidity increases.|
Topics: Carbon Nanotubes, Materials Science, Metamaterials, Nanotechnology
Learning from your mistakes is a key life lesson, and it's one that researchers at Pacific Northwest National Laboratory (PNNL) can attest to. After unintentionally creating carbon-rich nanorods, the team realized its accidental invention behaves weirdly with water, demonstrating a 20-year old theory and potentially paving the way to low-energy water harvesting systems and sweat-removing fabrics.
The researchers note that ordinarily materials will absorb more water as the humidity in the air around them increases. But between 50 and 80 percent relative humidity, these nanorods will actually do the opposite and expel water, a behavior they say is not shared by any other material. Below that range, they behave as normal, so the process is reversible by lowering the humidity again.
"Our unusual material behaves a bit like a sponge; it wrings itself out halfway before it's fully saturated with water," says David Lao, PNNL research associate and creator of the material.
These nanorods were created by mistake while trying to fabricate magnetic nanowires, and the researchers decided to give the accidents a closer look. On examining them with a vapor analysis instrument, Satish Nune, one of the authors of the research paper, noticed that the structures were actually losing weight as the humidity increased.
Scientists accidentally create nanorods that harvest water from the air, Michael Irving