[photo from Flickr user jamescridland]
Solar cells aren’t cheap. The cost of turning the sun’s energy into usable electricity has been one of the main factors in keeping solar energy adoption rates down. However, a new method of producing cells developed by researchers at Stanford could lead to less costly and more efficient green energy production. Cells using quantum dots have been a subject of research for several years due to their potential for providing much more efficiency than traditional cells using materials like silicon. This is because regular cells can only capture a single part of the spectrum dependant on the material they are constructed from, whereas the very small dots on quantum dot cells can be adjusted in size to capture energy at different wavelengths. These types of cells are easier to make too, as the chemical reactions involved in their production are simpler than those used in building existing solar cells. Unfortunately, these solar panels have yet to live up to their high-efficiency promise, and researchers are working on ways to change that.
Stanford chemical engineering professor Stacey Bent, along with a team of researchers, found that, by adding a single layer of organic molecules less than a nanometer thick, the efficiency of these quantum dot cells can be tripled. The type of organic molecule used is not important, which surprised Bent.
“We thought it would be very sensitive to what we put down,” Bent said in this article on PhysOrg.com.
Right now, the team has only been able to achieve about 0.4 percent efficiency, which doesn’t compare favorably with the 31 percent efficiency of traditional cells. The group plans on adjusting elements of the cell to hopefully bring this number up in the future, challenging traditional solar cells with less costly, more efficient alternatives.
[via PhysOrg.com, ACS Nano]
