CORVALLIS, US: Inkjet printers, a low-cost technology that in recent decades has revolutionized home and small office printing, may soon offer similar benefits for the future of solar energy.
Engineers at Oregon State University have discovered a way for the first time to create successful “CIGS” solar devices with inkjet printing, in work that reduces raw material waste by 90 per cent and will significantly lower the cost of producing solar energy cells with some very promising compounds.
High performing, rapidly produced, ultra-low cost, thin film solar electronics should be possible, scientists said.
The findings have been published in Solar Energy Materials and Solar Cells, a professional journal, and a patent applied for on the discovery. Further research is needed to increase the efficiency of the cell, but the work could lead to a whole new generation of solar energy technology, researchers said.
“This is very promising and could be an important new technology to add to the solar energy field. Until now no one had been able to create working CIGS solar devices with inkjet technology,” said Chih-hung Chang, an OSU Professor in the School of Chemical, Biological and Environmental Engineering.
Part of the advantage of this approach, Chang said, is a dramatic reduction in wasted material. “Some of the materials we want to work with for the most advanced solar cells, such as indium, are relatively expensive,” Chang said. “If that’s what you’re using you can’t really afford to waste it and the inkjet approach almost eliminates the waste.”
One of the most promising compounds and the focus of the current study is called chalcopyrite, or “CIGS” for the copper, indium, gallium and selenium elements of which it’s composed. CIGS has extraordinary solar efficiency.
In the new findings, researchers were able to create an ink that could print chalcopyrite onto substrates with an inkjet approach, with a power conversion efficiency of about 5 per cent. The OSU researchers say that with continued research they should be able to achieve an efficiency of about 12 per cent, which would make a commercially viable solar cell.
In related work, being done in collaboration with Greg Herman, an OSU Associate Professor of chemical engineering, the engineers are studying other compounds that might also be used with inkjet technology and cost even less.
“In summary, a simple, fast and direct-write, solution-based deposition process is developed for the fabrication of high quality CIGS solar cells,” the researchers wrote in their conclusion. “Safe, cheap, and air-stable inks can be prepared easily by controlling the composition of low-cost metal salt precursors at a molecular level.”
This work was supported by the Daegu Gyeongbuk Institute of Science and Technology, the U.S. Department of Energy and OSU’s University Venture Development Fund, which helps donors receive tax benefits while sponsoring projects that will bring new technology, jobs and economic growth to Oregon.
(C) Oregon State University News