University of Illinois at Chicago
chemist Luke Hanley is a big believer in harnessing solar energy to produce
electricity. Doing it more efficiently is his goal.
“If you could make solar cells cheaper and more
efficient, then you could think about putting them on a much wider variety of surfaces,”
said Hanley, professor and head of chemistry at the University
of Illinois at Chicago.
“There’s only a certain amount of energy that falls
from the sun per square meter. You can’t increase that amount of energy, but
you can make it less expensive to capture it,” he said.
Hanley received a $390,000 grant from the National Science
Foundation to test methods of coating solar panel films using nanoparticles
from a chemical group called metal chalcogenides. The inexpensive films could
be wrapped over everything from vehicles to buildings to gain maximum sunshine
exposure and produce electricity.
Chalcogenides are fairly abundant, relatively cheap, and
don’t contain toxic elements like cadmium or tellurium, which are often used in
solar cells.
“Using less expensive, less toxic materials—and using
processes where you could coat inexpensively and not use much of the material—could
make these solar cells more viable,” Hanley said.
Working with Igor Bolotin, research assistant professor of
chemistry, and graduate students Mike Majeski and Doug Pleticha, Hanley
developed a method for depositing metal chalcogenide nanoparticles by cluster
beam deposition. The process uses a magnetically confined electrical discharge
of argon gas ions to knock metal atoms into the gas phase and react with
hydrogen sulfide or hydrogen selenide. The metal-sulfide or metal-selenide then
condenses into nanosized clusters that land on a surface to produce the film.
“If you can do everything from the gaseous deposition
stage, you might make the process less expensive,” Hanley said. “You also may
make a novel material that has a better efficiency.”
Hanley and his coworkers will evaluate the electrical
properties of these new films and study how they respond to light. He thinks
that using different chemicals for nanoparticle-embedded solar films could
create new products some two to three times more efficient than products now on
the market, making solar energy more competitive.
But Hanley noted there are other factors to consider besides
price.
“Fossil fuels will always have an associated
environmental cost,” he said, while the sun does not.
“So, there’s a great long-term interest in solar energy.”