“Sun-Believable” is what the Notre Dame chemists call their invention. What they’ve made is a paste consisting of quantum dots – nano-particles of semiconductors – of titanium dioxide coated in either cadmium sulfide or cadmium selenide and suspended in a water-alcohol mixture. Brushed onto a transparent conducting material and exposed to light, this stuff produced 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,” Prashant Kamat, who’s leading the research at Notre Dame’s Center for Nano Science and Technology, said in a statement. “But this paint can be made cheaply and in large quantities. If we can improve the efficiency somewhat, we may be able to make a real difference in meeting energy needs in the future.”