This solar "paint" would have the same function as the large photovoltaic (PV)
solar collectors on buildings and "solar farms" around the world.
Korgel describes the tiny collection devices as a "solar sandwich."
"So these devices are 'sandwiches,' where you have the metal contact on the bottom and metal contact on the top to extract the charge out; and the middle part is the part that absorbs out the light," explains Korgel.
This paint, made of the CIGS nanocrystals, can be sprayed on plastic, glass and even fabric to create a solar cell.
"So what we're able to do is create radically new ways of depositing inorganic films to make solar cells, and so we're trying to meet this challenge of much lower cost of manufacturing," he says.
One way to create these cells on a very large scale would be to print them on thin, flexible sheets, the same way huge presses now print newspapers. "And the final product would ideally look something like today's shingles," says Vahid Akhavan, one of Korgel's graduate research assistants. "You want to produce something that is very user friendly. So you could go to your local hardware store, buy them and install them on your roof."
These shingles would do double duty, generating electricity while serving as roofing material. They would be also stand up better in bad weather, such as hail and windstorms, than some of today's more fragile
solar collectors.
A lot of challenges need to be conquered before
solar energy becomes so commonplace. High on that list is improving the efficiency of these nanomaterial cells. "Right now, we have made devices that have an efficiency of 3 percent, and to be commercial, you really need to be at 10 percent," says Korgel. "But I think we can get to 10 percent. Those are just engineering challenges; they are not necessarily easy, but they are not fundamental roadblocks."
