Silver nanowires have become the all-purpose solution for various display technologies, including flexible displays and OLEDs. But silver nanowires still have a bit of an Achilles Heel: they can be easily damaged by strong UV radiation and harsh environmental conditions.
Now researchers at Purdue University have turned to the other all-purpose nanomaterial—graphene—to use as a barrier layer on the outside of silver nanowires to protect them from UV radiation.
Earlier this year, Purdue researchers coated copper nanowires with graphene to lower their resistance and susceptibility to heat. But this latest research, published in the journal ACS Nano, actually stems from work that was started back in 2013 in which silver nanowires were coated with graphene primarily to address the issues of too much electrical resistance in the nanowires and too much electrical conductivity in the graphene.
Now this same hybrid combination of materials is seen as a protective coating.
"We show that even if you have only a one-atom-thickness material, it can protect from an enormous amount of UV radiation damage," said Gary Cheng, an associate professor at Purdue University, in a press release.
In tests, the researchers demonstrated that the graphene coating protected the nanowires from 2.5 megawatts of energy intensity per square centimeter from a high-energy laser, which would have vaporized the unsheathed nanowires.
The researchers believe that this development could lead to silver nanowires finding commercial applications in solar cells, flexible displays for computers and consumer electronics.
"Radiation damage is widespread," Suprem Das, who led the research, in a press release. "The damage occurs in medical imaging, in space applications and just from long-term exposure to sunlight, but we are now seeing that if you wrap silver nanowires with graphene you can overcome this problem."