Solar cell absorbs high-energy light at 30-fold higher concentration than conventional cells
y combining designer quantum dot light-emitters with spectrally matched photonic mirrors, a team of scientists with Berkeley Lab and the University of Illinois created solar cells that collect blue photons at 30 times the concentration of conventional solar cells, the highest luminescent concentration factor ever recorded. This breakthrough paves the way for the future development of low-cost solar cells that efficiently utilize the high-energy part of the solar spectrum.
“We’ve achieved a luminescent concentration ratio greater than 30 with an optical efficiency of 82-percent for blue photons,” says Berkeley Lab director Paul Alivisatos, who is also the Samsung Distinguished Professor of Nanoscience and Nanotechnology at the University of California Berkeley, and director of the Kavli Energy Nanoscience Institute (ENSI), was the co-leader of this research. “To the best of our knowledge, this is the highest luminescent concentration factor in literature to date.”
Alivisatos and Ralph Nuzzo of the University of Illinois are the corresponding authors of a paper in ACS Photonics describing this research entitled “Quantum Dot Luminescent Concentrator Cavity Exhibiting 30-fold Concentration.” Noah Bronstein, a member of Alivisatos’s research group, is one of three lead authors along with Yuan Yao and Lu Xu. Other co-authors are Erin O’Brien, Alexander Powers and Vivian Ferry.
The solar energy industry in the United States is soaring with the number of photovoltaic installations having grown from generating 1.2 gigawatts of electricity in 2008 to generating 20-plus gigawatts today, according to the U.S. Department of Energy (DOE). Still, nearly 70-percent of the electricity generated in this country continues to come from fossil fuels. Low-cost alternatives to today’s photovoltaic solar panels are needed for the immense advantages of solar power to be fully realized. One promising alternative has been luminescent solar concentrators (LSCs).