A new type of potentially low-cost solar cell that is twice as efficient as traditional organic solar cells—and may even rival silicon flat-panel cells—has been patented by research professors in the Center for Nanotechnology and Molecular Materials at Wake Forest University (Winston-Salem, NC). FiberCell, a Winston-Salem spinoff of the nanotechnology center, has already licensed the technology for commercialization and has successfully fabricated lightweight and flexible solar-cell modules using inexpensive roll-to-roll and spray-on techniques.
The solar cell is made using millions of tiny plastic optical fibers that collect light at oblique angles, prolonging the efficient collection of sunlight from early morning through evening hours. The fiber structure is composed of polymethylmethacrylate or perfluorocyclobutyl aligned optical fibers followed by an interior indium tin oxide (ITO)-based transparent conductor layer and a polythiophene:butyric acid methyl ester absorptive cladding layer. An aluminum external reflector and contact along the outside of the fibers funnels incoming light down the fiber, where photons are absorbed by the cladding layer and converted to electrons. Prototype 10 × 10 cm solar panels have been fabricated and are now undergoing testing at other laboratories. Contact David Carroll at [email protected].