Last week I wrote about how researchers at the University of Texas used carbon nanotubes (CNTs) to make objects invisible.
Now scientists at Stanford found another groundbreaking application for the material.
In short, researchers discovered that CNTs can be used to develop a high-tech sensor that promises to revolutionize a wide array of industries – from capacitive touchscreens on smartphones, to skin transplants. Seriously.
And while the technology behind this new sensor is complex, here’s a basic rundown of how they designed this new breakthrough.
The Wonders of “Conductive Spaghetti”
Basically, the process starts with spraying a liquid version of CNTs onto a layer of silicone.
Scientists then stretch the silicon out, forcing the nanotubes to expand. When they release the silicone, the CNTs end up forming miniature springs. Then they repeat the process on the other side, creating another group of nanotube springs.
To finish the sensor, researchers sandwich two of these silicone pieces together with the CNTs facing in.
Once it’s done, you’re left with a transparent sensor that’s…
Pressure-Sensitive: The nanotube springs act as touch-sensitive electrodes, which Darren Lipomi of the research team calls “conductive spaghetti.” So once either side of the silicone sandwich is pressed, the springs can immediately pick up on the touch and relay the input accordingly. Much like a touchscreen on a smartphone.
But unlike standard touchscreens, the sensor can detect varying amounts of pressure, too. According to Lipomi, the “sensor can register pressure ranging from a firm pinch between your thumb and forefinger to twice the pressure exerted by an elephant standing on one foot.”
Flexible: Once the initial stretching is completed, you can expand the material to two times its normal dimensions. It will simply snap back into formation afterwards without affecting the shape of the new nanotube springs. Which means the pressure sensitivity won’t degrade, either.
Versatile: Adding flexibility and pressure sensitivity to touch surfaces has a lot of potential.
Imagine, for instance, a huge display that you can roll up and take to an office meeting or a construction site… Or a flexible and durable screen that the military can use to strategize in a pinch, then crumple up and toss in a bag for later use.
The ability for the sensor to detect pressure opens up even more cutting-edge possibilities, though.
As Lipomi says, “One of the long term applications is to use a stretchable, conformable, skin-like device in artificial intelligence systems. So if you have a robot – like Data from Star Trek – his skin could be made out of something like this.”
Pretty cool. But the most game-changing application in my opinion is its potential use as an artificial skin graft. “The ultimate dream of this type of research is to restore functionality to lost skin for amputees, for injured soldiers, [and] burn victims.”
Now we’re talking!
And better yet, they’ve already developed the technology to improve the sensitivity of the synthetic skin even more.
Fake Skin That Can Feel the Weight of a Fly
According to the head of the research team, Professor Zhenan Bao, this study “focused on making [the sensor] stretchable and transparent.” But another sensor they designed prior to the current device is sensitive enough to detect the weight of a fly.
She thinks that with just a few modifications, they can apply the same level of sensitivity to the new sensor. Which would make it an even more effective skin transplant alternative. And it can be wired directly to the body’s nervous system.
Professor Bao says that “in a couple of years… electrical pulses from the sensors could be sent to skin areas that are intact.” So healthy skin surrounding the synthetic transplant would pick up the sensation.
Adding, “In the future, we would like to directly connect the electrical signals to the nervous system.” That way, patients would receive feeling from the sensor itself, just like normal skin.
Bottom line: Stanford’s new application for CNTs is bound to generate interest from a variety of industries. And you can bet that once researchers inch closer to a market-ready design – and prove its ability to effectively replace damaged skin – there won’t be a shortage of companies begging to license the technology.