Right here comes the Faraday cloth


You don't have to dive into 5G conspiracy theories to believe that you could deal with a little less radiation in your life. One way to block radiation is to use a Faraday cage, but this is usually a metal grid that makes everyday use difficult. Drexel University researchers managed to create a Faraday fabric by infusing ordinary cotton with a blend called MXene – which means your aluminum foil hat will soon be much more comfortable.

Faraday cages work because certain metals block the radiation in radio frequencies, but because of its wavelength, the metal doesn't even have to be solid – it can be a rigid cage or a flexible mesh. Many facilities are lined with such materials to prevent external radiation from interfering with sensitive measurements. More recently, however, companies like Silent Pocket have incorporated nets into bags and cases that completely isolate devices from incoming signals.

Let's be honest here and let's say this is definitely borderline paranoia. RF radiation is not harmful at the doses and frequencies we receive, and the FCC ensures that no device exceeds certain thresholds. However, there is also the possibility that your phone or laptop could naively connect to public WiFi, have its MAC number overflown by other devices, and otherwise interact with the environment in ways you may not like. And frankly … with the amount of devices currently emitting radiation, who wouldn't mind cutting their dose a little just to be completely safe?

This could be a lot easier in the near future, as Yury Gogotsi and his team at Drexel Nanomaterials Institute, of which he is director, have found a way to coat ordinary textile fibers with a metal compound that makes them Faraday cages – but also flexible, durable and washable.

The material they call MXene, which is a category rather than a single compound, is useful in many ways and is the subject of dozens of work by the team – this is just the newest application.

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

Credit: Drexel University

MXene are conductive metal-carbon compounds that can be produced in all possible forms: solid, liquid, even sprays. In this case, it's a liquid – a solution of tiny MXene flakes that easily adhere to the fabric and create a Faraday effect that, in tests, blocks 99.9% of RF radiation. After sitting around (maybe forgotten in a lab cupboard) for a few years, they retained 90% of their effectiveness, and the treated fabric is also safe to wash and wear.

You wouldn't necessarily want to wear a full suit, but this would make it easier for clothing to slip an RF blocking pocket into 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 of course be a popular item among conspiracy theorists.

It's still a long way from being in the rack, but Gogotsi was optimistic about the prospects for commercialization and noted that Drexel has several patents on the material and its uses. Other ways of infusing fabric with MXenen could result in clothing that also generates and stores energy.

More information on this particular application of MXenes can be found in the magazine Carbon.


Melinda Martin