Photo from CORE-Materials/Flickr
By Kevin Matyi and Tibian Ahmed
Graphene layered on common glass can potentially lead to cheaper solar panels and touch screens, a research paper released by scientists at Brookhaven National Laboratory on Feb. 12, 2016 shows.
The new properties allow for graphene to be used as a transparent conducting layer, similar to the display of a touchscreen.
“The scientific findings we have done and reported in our paper, will have an impact on research and development of new types of consumer electronic devices in the future,” Nanditha Dissanayake, senior scientist of Voxtel Inc. and co-author of the research paper, said.
Currently, touchscreens use a material known as indium tin oxide, which is expensive due to the rarity of the element indium, “so people are actively seeking replacements for ITO and there are lots of people who have thought graphene would potentially make a good replacement,” Professor Matthew Eisaman of Stony Brook University said.
“[Common] glass is low cost, commercially available and so you can imagine applications in consumer electronics and outside of solar cells,” Eisaman said.
“Graphene is, very simply, a single atomic layer of graphite,” Carl Ventrice Jr., Associate Professor of Nanoscience at the Colleges of Nanoscale Science and Engineering at SUNY Polytechnic Institutes, said.
“Roughly 97 percent of visible light that hits the single atomic layer of graphene will just pass right through,” he said.
It will also be safer, as some current solar cells have a layer of cadmium sulfide on top, which is toxic to humans, while graphene is simply carbon.
“The idea, initially, was ‘let’s replace those top layers with graphene,’ so instead of the cad-sulfide layer, you put graphene directly on the CIGS,” Eisaman said, referring to the type of solar cell he was using.
During the experiment, the graphene went through a process known as doping, where extra chemicals are added to a material in order to control its electrical properties.
“If you dope things by adding external chemicals, those chemicals can react, they can evaporate, and so over time that doping can go away,” Eisaman said. “When you use the sodium in [the glass], it’s kind of like having an infinite reservoir of doping atoms.”
“You can now use it to dope graphene strongly, and, importantly, persistently, which means it doesn’t degrade over time,” he said.
Now electronics can stay functional forever and become cheaper, as more expensive components are replaced with common glass and graphene.
“[As] solar power is becoming a more and more viable option for energy to replace traditional fossil fuels, it will inevitably affect all of us,” Saddmun Ahsan, a graduate chemical engineering student at Cornell University, said.
“Since glass costs account for a large portion of solar cell price, and they’re using the cheapest available glass this is great news for the solar industry,” Lucas Smith, a 24-year-old graduate student of medicinal chemistry at SUNY Buffalo State, said.
Christina Mathieson, Marketing Vice President from Sunation, a solar panel company on Long Island, said that the company currently uses “really proven technology that’s been around for 20 or 30 years.”
Despite existing for several decades, as of 2011, solar power only accounted for 0.5 percent of global energy demand, according to the Center for Climate and Energy Solutions.
Ventrice said that using graphene as the transparent conducting layer is potentially the most important application, and works really well.
“The most significant part is the ramifications it has for the semiconductor industry,” Ahsan said. “By enhancing doping, which is essential for the industry, we can expect to see future cost cutting and greater effects throughout the industry.”
As costs reduce throughout the solar industry, solar energy cells could become much more widespread.
“As a single energy source, solar is the only renewable energy which could supply the whole planet on its own in the coming decades,” Smith said.