Faraday fabrics?

December 11, 2020

Researchers at Drexel University's College of Engineering have reported that fabric coated with a conductive, two-dimensional material called MXene, is highly effective at blocking electromagnetic waves and potentially harmful radiation. The discovery is a key development for efforts to weave technological capabilities into clothing and accessories.

Materials that block electromagnetic waves had a commercial moment a handful of years ago when fears that high-tech thieves could scan or copy credit cards, passports or hack into laptops and contactless car keys had people putting them in special wallets, bags and protected pockets. While reporting suggests these fears were overblown, the demand for this sort of textile is likely to grow as more manufacturers incorporate sensing and communication technologies into fabrics.

They could also be deployed in national defense organizations to shield devices from tracing and hacking and to protect people from strong microwave radiation - the kind that might have been used against American and Canadian diplomats according to recent reports.

"Wearable devices will need shielding from the electromagnetic interference (EMI) regularly produced by mobile devices, and that shielding should be integrated as part of the garment," said Yury Gogotsi, PhD, Distinguished University and Bach professor at Drexel, who led research recently published in the materials science journal CARBON. "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."

The interference comes from residual electromagnetic fields produced by electronics devices. Users notice it as a buzz, a slowing or temporary stall in a device's function. It's a momentary inconvenience, but these moments are becoming more frequent with expanded use of mobile devices and connected technology - including wearables.

Improving the design of these devices, according to Gogotsi, entails using a shielding material to contain electromagnetic field generated by the device, as well as protecting it from interference produced by other devices. Gogotsi's team, which first produced and studied the conductive two-dimensional MXene materials nearly a decade ago, has been testing MXene coatings for this role, with promising results.

"MXenes are well-suited for use as shielding because they can be stably produced as a spray coating, an ink or a paint, so they can be applied to textiles without adding much weight or taking up more room," Gogotsi said. "We have also discovered that MXene shielding can absorb and reflect electromagnetic waves, so it not protects the wearable devices and electronic gadgets, but also protect people from strong electromagnetic field."

The researchers' most recent finding shows that dip-coating regular cotton or linen fabric in a MXene solution will turn it into an equally formidable shielding material - blocking EMI at greater than 99.9% effectiveness.

MXene flakes suspended in solution naturally adhere to the fibers in conventional cotton and linen fabrics because of their electric charge. This produces a thorough and durable coating, without the need for the pre- or post-treatment processes to produce most commercial conductive yarns and fabrics.

As part of the study, the MXene-coated fabrics were tested after being stored under normal conditions for two years and they showed only a slight drop in shielding efficiency - roughly 10%.

"This work provides a much-improved alternative to current EMI shielding textiles," said Simge Uzun, a doctoral student in Gogotsi's research group, who conducted this research as a part of her PhD program. "Not only do MXene-coated fabrics exceed the performance of commercial metal-coated fabrics, but they can be sustainably produced by coating form aqueous solution without extra processing or chemical additives."
-end-


Drexel University

Related Mobile Devices Articles from Brightsurf:

How mobile apps grab our attention
Aalto University researchers alongside international collaborators have done the first empirical study on how users pay visual attention to mobile app designs.

No association found between exposure to mobile devices and brain volume alterations in adolescents
New study of 2,500 Dutch children is the first to explore the relationship between brain volume and different doses of radiofrequency electromagnetic fields

Mobile devices blur work and personal privacy raising cyber risks, says QUT researcher
Organisations aren't moving quickly enough on cyber security threats linked to the drive toward using personal mobile devices in the workplace, warns a QUT privacy researcher.

Multi-mobile (M2) computing system makes android & iOS apps sharable on multiple devices
Computer scientists at Columbia Engineering have developed a new computing system that enables current, unmodified mobile apps to combine and share multiple devices, including cameras, displays, speakers, microphones, sensors, and GPS, across multiple smartphones and tablets.

The use of mobile phone and the development of new pathologies
Professor Raquel Cantero of the University of Malaga (UMA) has identified a generational change in the use of this finger due to the influence of new technologies.

Mobile devices don't reduce shared family time, study finds
The first study of the impact of digital mobile devices on different aspects of family time in the UK has found that children are spending more time at home with their parents rather than less -- but not in shared activities such as watching TV and eating.

Mobile, instant diagnosis of viruses
In a first for plant virology, a team from CIRAD recently used nanopore technology to sequence the entire genomes of two yam RNA viruses.

Wearable devices and mobile health technology: one step towards better health
With increasing efforts being made to address the current global obesity epidemic, wearable devices and mobile health ('mHealth') technology have emerged as promising tools for promoting physical activity.

Mobile health devices diagnose hidden heart condition in at-risk populations
New research shows wearable mobile health devices improved the rate of diagnosis of a dangerous heart condition called atrial fibrillation.

Ultrasound-firewall for mobile phones
Mobile phones and tablets through so-called audio tracking, can be used by means of ultrasound to unnoticeably track the behaviour of their users: for example, viewing certain videos or staying in specific rooms and places.

Read More: Mobile Devices News and Mobile Devices Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.