Here comes the Faraday fabric

You don’t have to buy into 5G conspiracy theories to think that you could do with a little less radiation in your life. One way of blocking radiation is a Faraday cage, but this is usually a metal mesh of some kind, making everyday use difficult. Researchers at Drexel University have managed to create a Faraday fabric by infusing ordinary cotton with a compound called MXene — meaning your tinfoil hat is about to get a lot comfier.

Faraday cages work because radiation in radio frequencies is blocked by certain metals, but because of its wavelength, the metal doesn’t even have to be solid — it can be a solid cage or flexible mesh. Many facilities are lined with materials like this to prevent outside radiation from interfering with sensitive measurements, but recently companies like Silent Pocket have integrated meshes into bags and cases that totally isolate devices from incoming signals.

Let’s be frank here and say that this is definitely paranoia-adjacent. RF radiation is not harmful in the doses and frequencies we get it, and the FCC makes sure no device exceeds certain thresholds. But there’s also the possibility that your phone or laptop is naively connecting to public Wi-Fi, getting its MAC number skimmed by other devices, and otherwise interacting with the environment in a way you might not like. And honestly… with the amount of devices emitting radiation right now, who wouldn’t mind lowering their dose a little, just to be extra sure?

That may be much easier to do in the near future, as Yury Gogotsi and his team at the Drexel Nanomaterials Institute, of which he is director, have come up with a way to coat ordinary textile fibers in a metallic compound that makes them effective Faraday cages — but also flexible, durable and washable.

The material, which they call MXene and is more of a category than a single compound, is useful in lots of ways, and the subject of dozens of papers by the team — this is just the most recent application.

“We have known for some time that MXene has the ability to block electromagnetic interference better than other materials, but this discovery shows that it can effectively adhere to fabrics and maintain its unique shielding capabilities,” said Gogotsi in a news release. You can see the fabric in action on video here.

Image Credits: Drexel University

MXenes are conductive metal-carbon compounds that can be fabricated into all sorts of forms: solid, liquid, even sprays. In this case it’s a liquid — a solution of tiny MXene flakes that adhere to the fabric quite easily and produce a Faraday effect, blocking 99.9% of RF radiation in tests. After sitting around for a couple years (perhaps forgotten in a lab cupboard) it kept 90% of their effectiveness, and the treated fabric can also be washed and worn safely.

You wouldn’t necessarily want to wear a whole suit of the stuff, but this would make it easier for clothing to include an RF-blocking pocket in a jacket, jeans or laptop bag that doesn’t feel out of place with the other materials. A hat (or underwear) with a layer of this fabric would be a popular item among conspiracy theorists, of course.

It’s still a ways from showing up on the rack, but Gogotsi was optimistic about its prospects for commercialization, noting that Drexel has multiple patents on the material and its uses. Other ways of infusing fabric with MXenes could lead to clothes that generate and store energy as well.

You can read more about this particular application of MXenes in the journal Carbon.