Dec 8 2010
Researchers from the Ames Lab and Iowa State University have created a new technology, which would produce a uniform and thin, light assimilating layer on textured substrates thereby improving the effectiveness of Polymer solar cells and increasing their light absorption capabilities.
According to an Iowa State Assistant Professor, Sumit Chaudhary, who is also an associate of the US Department of Energy’s Ames Laboratory and a computer engineer, the new process traps the light and increases solar efficiency by 20%. The detailed description of this fabrication technology was recently printed online by the Journal Advanced Materials. He further mentioned that it was essential to locate a textured substrate pattern that permits a light absorbing layer to set uniformly even on flat top ridges that go up and down, resulting in polymer solar cells capturing maximum light within the ridges. The tests demonstrated that when compared to flat cells the light captured at the near Infrared band edge was 100 % more.
Along with Chaudhary, Joong-Mok Park, an assistant Scientist at Ames Laboratory, Kai-Ming Ho, an Ames Laboratory faculty scientist and an Iowa State Distinguished Professor of Astronomy and Physics; and Kanwar Singh Nalwa, a student associate of the Ames Laboratory and a graduate student in electrical and computer engineering work on the solar cell project. The finance for the research was provided by the IOWA Power Fund, DOE’s office of Basic Energy Sciences and the Ames Laboratory.
Chaudhary disclosed that the idea was already used on Silicon based solar cells but previous usage of textured substrate in Polymer Solar Cells had been unsuccessful as they need added processing steps or more advanced coating technologies. Either too thin layer over the ridges were produced or too thick a layer over the valleys were obtained resulting in short circuits at the ridges and valleys leading to a poor solar efficiency. Nalwa commented that to get more power from the solar cell both the solution based coating and substrate texture must be exactly right. The Iowa State University Research Foundation has applied for a patent for its substrate coating technology and is also trying to license the process to solar cell manufacturers.
Source: http://www.techtransfer.iastate.edu/