Researchers at the University of Illinois at Urbana-Champaign use a printing process to assemble tiny cells into multilayer stacks for extraordinary levels of photovoltaic conversion efficiency.
They developed a printing approach that allows manipulation of ultrathin, small semiconductor elements that can be stacked on top of one another to yield an unusual type of solar cell capable of operating across the entire solar spectrum at exceptionally high efficiency.
“The strategy involves high-speed, printing-based manipulation of thin, microscale solar cells and new interface materials to bond them into multilayer stacks,” Rogers, a Swanlund Chair and professor of materials science and engineering explained. “Quadruple-junction, four-terminal solar cells that we can build in this way have individually measured efficiencies of 43.9 percent.”
“This is a high-throughput, parallel assembly process that allows for simultaneous formation of arrays of stacked multi-junction cells in a fully automated step-and-repeat mode with high yields—greater than 95 percent—and accurate overlay registration. A newly developed interfacial material for these stacks enables ideal optical, electrical, and thermal properties. ” stated Xing Sheng, a postdoctoral fellow with Rogers’ research group and first author of the paper, “Printing-based assembly of quadruple-junction four-terminal microscale solar cells allows realization of extremely high-efficiency modules,” published this week in the journal Nature Materials.
“This is very nice work. The results are impressive, and the schemes appear to provide a route to ultra-high efficiency photovoltaics, with strong potential for utility-scale power generation,” stated Ali Javey, a professor of electrical engineering and computer sciences at the University of California, Berkeley.
Javey, who is a program leader for electronic materials at the Lawrence Berkeley National Laboratory and a co-director of the Bay Area Photovoltaics Consortium, was not involved with this research.