University of Arkansas researchers are working on a promising new material to create more efficient photovoltaic solar cells to be used in space missions.
Shui-Qing 'Fisher' Yu, associate professor of electrical engineering, will serve as principal scientific investigator on the multi-institutional project. The team will develop photovoltaic devices made of silicon-germanium-tin (SiGeSn), which has been proven to increase efficiency in electronic devices that source, detect and control light.
The project is made possible by a $750,000 NASA/EPSCoR grant to the Arkansas Space Grant Consortium Office at the University of Arkansas at Little Rock. EPSCoR (Experimental Program to Stimulate Competitive Research) is a funding program to increase state participation in competitive aerospace-related research activities.
"Now we have the opportunity to move forward developing a high-performance solar cell for space applications," says Yu.
Yu will collaborate with Hameed Naseem, professor of electrical engineering; Mansour Mortazavi, physics professor at the University of Arkansas at Pine Bluff; and Allan Thomas, physics professor at the University of Arkansas at Little Rock. Yu, Naseem and Mortazavi previously received a $725,000 grant from the US Air Force Office of Scientific Research to work on similar technology.
The researchers grow and characterize silicon-germanium-tin materials on silicon substrates using ultra-high-vacuum chemical vapor deposition. For the NASA project, the researchers will capitalize on their work with silicon-germanium-tin to develop photovoltaic devices that can be integrated into existing solar cells to achieve a more efficient, optimal energy yield. Existing triple-junction PV technology used by NASA has reached its efficiency limit, it is reckoned. The new material is intended to boost performance, helping NASA achieve its 15-year, 45% efficiency goal for solar devices. The new material should also lower the cost of manufacturing and make the devices more radiation tolerant.
The research plan includes device design and simulation, material growth and characterization, optical characterization of silicon-germanium-tin materials, and development of silicon-germanium-tin photoconductors.
Related to this research, Yu has also received a $96,455 grant from the US Army Research Office to upgrade equipment used to characterize silicon-germanium-tin-based devices.
