The W.M. Keck Foundation has awarded a $1 million grant to a team led by University of Texas at Austin chemists to develop an innovative new coating for silicon-based solar cells that could boost their efficiency by as much as 20%. It's a bold research challenge that, so far, no one else has figured out how to do -- but if successful, could make solar power generation cheaper.
Efficiency is a problem in silicon-based solar cells, which currently account for about 95% of the solar energy market and are critical components in everything from rooftop solar panels to the large panels used in commercial solar farms. They convert less than 30% of the energy in sunlight into electricity. About half of the lost energy is due to heat generation within the silicon cell.
"The goal of our project is to claw back some of this energy loss by chemically attaching organic dyes to the surface of the silicon cell that reduce heat losses and convert more of that energy into electricity," said Sean Roberts, the project's principal investigator and an assistant professor of chemistry at UT Austin.
When silicon absorbs a particle of light, called a photon, it uses its energy to excite an electron, but much of that electron's energy is lost as heat. The team is developing dye molecules that are unique because they use the energy of a photon to excite pairs of electrons -- not just one -- which allows more of the photon's energy to be converted into electricity. The basic idea to use such dyes has been around for 40 years, but so far, scientists have been unable to make it work. The real technical challenge is getting the pairs of excited electrons to flow into the silicon cell so they can be collected as current.
"Our solution is to use some synthetic approaches developed in Mike Rose's lab to chemically tether the dyes to the silicon surface, essentially building small wires that can allow electrons to flow between the materials," Roberts said.
"This is risky research," said Daniel Jaffe, UT Austin's vice president for research. "This kind of approach has been tried many times before but failed. That UT Austin and Keck are supporting a group of young scientists to try their hand at this says a lot. It says we support bold, innovative work that, if it succeeds, could have a huge payoff for both science and society."
UT Austin's Office of the Vice President for Research and College of Natural Sciences are also providing matching funds totaling $278,500.
The grant is awarded through the Keck Foundation's Science and Engineering Research Grant Program.
The Los Angeles-based W.M. Keck Foundation was established in 1954 by the late W.M. Keck, founder of Superior Oil Co. The foundation focuses its support on pioneering discoveries in science and engineering, medical research and undergraduate education.