WEST LAFAYETTE, Ind. - Researchers are creating a new type of solar cell designed to self-repair like natural photosynthetic systems in plants by using carbon nanotubes and DNA, an approach aimed at increasing service life and reducing cost.
"We've created artificial photosystems using optical nanomaterials to harvest solar energy that is converted to electrical power," said Jong Hyun Choi, an assistant professor of mechanical engineering at Purdue University.
The design exploits the unusual electrical properties of structures called single-wall carbon nanotubes, using them as "molecular wires in light harvesting cells," said Choi, whose research group is based at the Birck Nanotechnology and Bindley Bioscience centers at Purdue's Discovery Park.
"I think our approach offers promise for industrialization, but we're still in the basic research stage," he said.
Photoelectrochemical cells convert sunlight into electricity and use an electrolyte - a liquid that conducts electricity - to transport electrons and create the current. The cells contain light-absorbing dyes called chromophores, chlorophyll-like molecules that degrade due to exposure to sunlight.
"The critical disadvantage of conventional photoelectrochemical cells is this degradation," Choi said.
The new technology overcomes this problem just as nature does: by continuously replacing the photo-damaged dyes with new ones.
"This sort of self-regeneration is done in plants every hour," Choi said.
The new concept could make possible an innovative type of photoelectrochemical cell that continues operating at full capacity indefinitely, as long as new chromophores are added.
Findings were detailed in a November presentation during the International Mechanical Engineering Congress and Exhibition in Vancouver. The concept also was unveiled in an online article (http://spie.
|Contact: Emil Venere|