UW Professors Discover Method to Increase Solar Cell Efficiency
A group of University of Wyoming professors has discovered a way to dramatically improve the efficiency of solar cells.
Jinke Tang and Yuri Dahnovsky, professors in the Department of Physics and Astronomy; TeYu Chien, an assistant professor of physics and astronomy; and Wenyong Wang, an associate professor of physics and astronomy, found a way to increase solar cell energy conversion by 300 percent on average and up to 700 percent in some cases by adding manganese atoms to solar cells.
Their research paper, “Giant Photocurrent Enhancement by Transition Metal Doping in Quantum Dot Sensitized Solar Cells,” was published in Applied Physics Letters last fall and was recently highlighted again by the Department of Energy’s Office of Basic Energy Sciences.
Tang said the way solar cells work is by converting photons- particles of light- into electrons which are used to generate electricity.
“The main problem in converting the photons into electrons is when the photon is absorbed, an electron is generated, but this electron tends to quickly recombine with the host,” Tang said. “The idea is to prevent that recombination and extract that electron from the quantum dot into a semiconductor.”
Dahnovsky says the key component of their research is electron “tunneling,” which is a component of quantum mechanics. Electrons are able to tunnel between manganese and zinc atoms much easier than with zinc and lead atoms located at the boundary between a quantum dot- a very small semiconducting particle - and a semiconductor.
“We see a very strong increase of the efficiency for the electron to jump from a quantum dot to a semiconductor,” Dahnovsky said. “This feature, this property can significantly increase the efficiency of solar cells.”
Chien said the research could be used to help farmers and ranchers in rural areas like Wyoming gain access to electric power to aid in crops and livestock.
“Right now in Wyoming we have remote places and if you want to have electricity you need to be connected to the electric grid,” Chien said. “But sometimes it costs a lot of money to build that infrastructure.”
Chien said their research would provide a cheap option to provide locally generated electricity to a remote area. Farmers could use solar-powered sensors that could measure light, humidity, oxygen and temperature in their crop soil and ranchers could use solar panels to power a water pump to water their livestock.
You are independent from an electric grid,” Chien said.
The research was funded by the DOE, Office of Basic Energy Sciences, as part of the Established Program to Stimulate Competitive Research Program.