Civil War soldiers used the dye from purple pokeberries to write letters home. Now, the bright-colored weeds are being used for a far more modern purpose. Researchers at Wake Forest University’s Center for Nanotechnology and Molecular Materials created low-cost, fiber-based solar cells that work more efficiently when coated with a layer of pokeberry dye. Scientists hope the cheap solar cells combined with a common plant will help provide inexpensive electricity to developing nations.
Wake Forest researchers and their accompanying company, FiberCell Inc., are the first group to file a patent for fiber-based solar cells. To create the cells, scientists stamp plastic fibers onto large, plastic sheets, forming millions of tiny “cans” that trap light until it is absorbed. The fibers create a larger surface area so light can be collected at any angle from the time the sun rises until it sets. By coating the plastic sheets with a layer of purple pokeberry dye, the fibers can absorb even more sunlight to convert to power.
Designers say the plastic sheets can produce about twice as much power as current flat-cell technology. Because the plastic sheets are flexible and can be rolled up, scientists hope to ship the tech to developing nations like those in Africa. Workers could then coat the cells in dye from locally grown pokeberries. The system could create a low-cost and environmentally friendly method of providing electricity to those who normally live without power.