Haven’t you ever dropped your smartphone, ending with a cracked screen and cussing yourself for being so careless? Haven’t you ever thought the need for electronics that wouldn’t break easily? Turns out the future of electronics is everything you’ve ever wanted it to be!
One of the main reasons that electronic parts break is that they are made using materials that break easily. They are difficult to use in products that need bending, such as devices that can be attached or glued onto the skin. Moreover, clear or transparent materials or even heavy plastics aren’t known to conduct electricity well either. And this is probably why we haven’t seen wearable electronics yet.
However, researchers might just have come up with a solution that might make all your dreams come true. Researchers have developed a thin flexible mesh which can be used to conduct electricity and is transparent as well. This new mesh could be the basis of all kinds of products, says Sam Yoon, the lead researcher behind this project.
Yoon and his team started out with a material known as acrylonitrile, a clear liquid that has commonly been used to make thermoplastic composites. This material was mixed with another liquid which played the role of a solvent and the mix was squeezed through an incredibly tiny nozzle and sprayed through the air. The solvent evaporated upon being sprayed and the tiny acrylonitrile molecules ended up getting linked to each other, creating a high gravity compound called polyacrylonitrile. Continuous squeezing created a long polyacrylonitrile fiber which was so thin that it was almost invisible. In fact, the human hair is 17 times wider. Researchers also kept moving the nozzle back and forth, which helped them create a layer that resembled a spider’s web.
Sounds great, doesn’t it. However, like most other thermoplastic composites, polyacrylonitrile isn’t a conductor of electricity. So the most important step was to add metal to the coating so that electricity could flow through. Now since basic metal coatings couldn’t stick to polyacrylonitrile, researchers needed something different. To counteract this problem, they sprayed a coating of an inert metal like platinum or gold on the polyacrylonitrile compound. They then added another layer of polyacrylonitrile, offering temporary support, assisting the metal base to resist sagging.
This fiber covered frame was then connected to negatively charged electrodes and dipped in a solution which contained dissolved copper. Electric current was run through the solution for an entire minute during which time the copper got attracted to the fibers. This allowed the polyacrylonitrile to not only bond at places where they touched each other, but also made it possible to add a thin layer of copper which conducted electricity. This was then attached to a clear plastic which used adhesives the way band-aids do. The entire frame was then dipped in a liquid which dissolved polyacrylonitrile fibers which didn’t have copper jackets, leaving behind a mesh made purely using copper-coated fibers.
Younan Xia, a materials scientist at Georgia Institute Technology, states that it’s easy to understand why the mesh is so transparent. Xia also noted that the tinges of color added to the mesh could further be reduced by using silver instead of copper. Lab tests further proved that the mesh is not only flexible, but also managed to conduct electricity despite being bent more than a thousand times. It carried electricity after being stretched 6 times its length and none of the fibers showed signs of deformity.
In other words, this mesh could just be the jumpstart wearable tech needed. It could find great use as a flexible solar cell or as a sensor for artificial skin or artificial limbs. It could also be attached to the skin to monitor electrical currents. But perhaps, its most promising use is that it could also be used to create roll-up touchscreen displays!