Reshaping the Solar Spectrum to Turn Light to Electricity
http://ucrtoday.ucr.edu/30606[font face=Serif][font size=5]Reshaping the Solar Spectrum to Turn Light to Electricity[/font]
[font size=4]UC Riverside researchers find a way to use the infrared region of the suns spectrum to make solar cells more efficient[/font]
By Iqbal Pittalwala on July 27, 2015
[font size=3]RIVERSIDE, Calif. When it comes to installing solar cells, labor cost and the cost of the land to house them constitute the bulk of the expense. The solar cells made often of silicon or cadmium telluride rarely cost more than 20 percent of the total cost. Solar energy could be made cheaper if less land had to be purchased to accommodate solar panels, best achieved if each solar cell could be coaxed to generate more power.
A huge gain in this direction has now been made by a team of chemists at the University of California, Riverside that has found an ingenious way to make solar energy conversion more efficient.
The researchers report in
Nano Letters that by combining inorganic semiconductor nanocrystals with organic molecules, they have succeeded in upconverting photons in the visible and near-infrared regions of the solar spectrum.
The infrared region of the solar spectrum passes right through the photovoltaic materials that make up todays solar cells, explained Christopher Bardeen, a professor of chemistry. The research was a collaborative effort between him and Ming Lee Tang, an assistant professor of chemistry. This is energy lost, no matter how good your solar cell. The hybrid material we have come up with first captures two infrared photons that would normally pass right through a solar cell without being converted to electricity, then adds their energies together to make one higher energy photon. This upconverted photon is readily absorbed by photovoltaic cells, generating electricity from light that normally would be wasted.
Bardeen added that these materials are essentially reshaping the solar spectrum so that it better matches the photovoltaic materials used today in solar cells. The ability to utilize the infrared portion of the solar spectrum could boost solar photovoltaic efficiencies by 30 percent or more.
...[/font][/font]