University of Notre Dame researchers have developed an inexpensive energy-producing "solar paint" made from semiconducting quantum dots.
The team at Notre Dame's Center for Nano Science and Technology (NDnano) used the quantum dots to make a spreadable ‘solar paint’ that can be applied to any conductive surface without special equipment, said Prashant Kamat, John A. Zahm Professor of Science in Chemistry and Biochemistry, who led the team. The quantum dots, made from titanium dioxide, were coated with cadmium sulfide or cadmium selenide, and then suspended in a water-alcohol mixture to create a paste. When the paste was brushed onto a transparent conducting material and exposed to light, it created electricity.
"The best light-to-energy conversion efficiency we've reached so far is 1 percent, which is well behind the usual 10 to 15 percent efficiency of commercial silicon solar cells," explains Kamat. "But this paint can be made cheaply and in large quantities.” The team now is working to improve efficiencies.
The work appears in the journal ACS Nano. The research was funded by the U.S. Department of Energy's Office of Basic Energy Sciences.