Low-cost, high efficiency solar cells to be made from virtually any semiconductor material
A technology that would enable low-cost, high efficiency solar cells to be made from virtually any semiconductor material has been developed by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley. This technology opens the door to the use of plentiful, relatively inexpensive semiconductors, such as the promising metal oxides, sulfides and phosphides, that have been considered unsuitable for solar cells because it is so difficult to taylor their properties by chemical means.
“It’s time we put bad materials to good use,” says physicist Alex Zettl, who led this research along with colleague Feng Wang. “Our technology allows us to sidestep the difficulty in chemically tailoring many earth abundant, non-toxic semiconductors and instead tailor these materials simply by applying an electric field.”
Zettl, who holds joint appointments with Berkeley Lab’s Materials Sciences Division and UC Berkeley‘s Physics Department where he directs the Center of Integrated Nanomechanical Systems (COINS), is the corresponding author of a paper describing this work in the journal Nano Letters. The paper is titled “Screening-Engineered Field-Effect Solar Cells.” Co-authoring it were William Regan, Steven Byrnes, Will Gannett, Onur Ergen, Oscar Vazquez-Mena and Feng Wang.
Solar cells convert sunlight into electricity using semiconductor materials that exhibit the photovoltaic effect — meaning they absorb photons and release electrons that can be channeled into an electrical current. Photovoltaics are the ultimate source of clean, green and renewable energy but today’s technologies utilize relatively scarce and expensive semiconductors, such as large crystals of silicon, or thin films of cadmium telluride or copper indium gallium selenide, that are tricky or expensive to fabricate into devices.
“Solar technologies today face a cost-to-efficiency trade-off that has slowed widespread implementation,” Zettl says. “Our technology reduces the cost and complexity of fabricating solar cells and thereby provides what could be an important cost-effective and environmentally friendly alternative that would accelerate the usage of solar energy.”
via Science Daily
