Scientists invent double-pane solar windows powered by quantum dots

Jan. 2 (UPI) -- Researchers at the Los Alamos National Laboratory have designed efficient and cost-effective solar windows by combining quantum dot technology with a double pane structure.

The layers of quantum dots are tweaked to absorb only part of the solar spectrum, allowing the double-pane solar windows to generate energy while providing shade and insulation.

Scientists suggest the new technology will lower the cost of solar electricity.

"The approach complements existing photovoltaic technology by adding high-efficiency sunlight collectors to existing solar panels or integrating them as semitransparent windows into a building's architecture," lead researcher Victor Klimov said in a news release.

The new windows rely on a technology called "solar-spectrum splitting," which allows the panels to simultaneously absorb lower- and higher-energy solar photons. The technology prevents reabsorption, a phenomenon that diminishes panels' electrical output.

To enable solar-spectrum splitting, scientists installed quantum dots combined with manganese ions. When the quantum dots absorb the solar photons, the manganese impurities are activated, emitting energy at less than the quantum-dot absorption threshold. The technology almost entirely eliminates reabsorption.

The front surface of the first pane features manganese-doped quantum dots, while copper indium selenide quantum dots are layered on the back of the second pane. The first pane absorbs blue and ultraviolet light, while the back pane absorbs the rest of the spectrum.

Once absorbed, the quantum dots reemit a photon at a longer wavelength. The insides of the double pane trap and direct these wavelengths toward the window frame where solar cells convert the light into electricity.

Researchers described the novel technology this week in the journal Nature Photonics.