Two-Dimensional Material Now Easier To Manufacture

We often see scientific breakthroughs in journals or other media that’s reported on as if it’s a revolutionary technology guaranteed to reshape human existence, only to never hear about it again. A more cynical reason for this phenomenon is a certain amount of clickbait or engagement farming, but the real culprit often tends to be the discovery of a process that can’t produce the new material or effect at a scale that makes sense for mass production. One of those are MXenes (“max-enes”), a two-dimensional material first produced over a decade ago, but new research into them has developed a much more efficient way of producing them.

Before this discovery, these materials were produced in a convoluted process involving the MXene precursor materials, combining them with an etchant, washing them off, and then repeatedly spinning them in a centrifuge to separate out unwanted byproducts. As one can imagine, this doesn’t produce material in an industrial quantity. But the new method uses a vapor deposition process which simplifies the precursor steps using less expensive materials, as well as skips the etching step. After that, the researchers have found that the MXenes can grow in a much more controlled way, allowing for greater production amounts and higher quality.

In the intervening years since their discovery and first synthesis MXenes have shown potential for wide-ranging applications, from battery production to antennas to water purification. Another interesting application is as a switchable Faraday cage, as we’ve covered in the past. Hopefully the slow plod of scientific discovery continues and we can start seeing more of these incremental gains improving our lives, even if we don’t get a sudden technological revolution from it.

MXenes Make Faraday Cages You Can Turn On And Off

Shielding is crucial for all manner of electronic devices. Whether you want to keep power supply noise out of an audio amplifier, or protect ICBMs against an electromagnetic pulse from a nuclear attack, the basic physics behind shielding remains the same. A Faraday cage or shield will do the trick.

At times, though, it would be desirable to shield and unshield a device at will. A new class of materials known as MXenes may be able to offer just that functionality, with microscopically thin films serving as shields that can be switched on and off at will.

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Antennas That You Install With A Spray-Can

With the explosion in cell phones, WiFi, Bluetooth, and other radio technologies, the demand for antennas is increasing. Everything is getting smaller and even wearable, so traditional antennas are less practical than ever. You’ve probably seen PCB antennas on things like ESP8266s, but Drexel University researchers are now studying using titanium carbide — known as MXene — to build thin, light, and even transparent antennas that outperform copper antennas. Bucking the trend for 3D printing, these antennas are sprayed like ink or paint onto a surface.

A traditional antenna that uses metal carries most of the current at the skin (something we’ve discussed before). For example, at WiFi frequencies, a copper antenna’s skin depth is about 1.33 micrometers. That means that antennas have to be at least thick enough to carry current at that depth from all surfaces –practically 5 micrometers is about the thinnest you can reasonably go. That doesn’t sound like a lot, but when you are trying to make something thin and flexible, it is pretty thick. Using MXene, the researchers made antennas as thin as 100 nanometers thick — that’s 10% of a micrometer and only 2% of a conventional antenna.

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