U.S. scientists develop quantum-dot coating that can turn windows into solar panels

LOS ALAMOS, NEW MEXICO — Researchers at the Los Alamos National Laboratory in New Mexico have developed a film of quantum dots that can turn windows into photovoltaic systems.

Quantum dots can be used as semiconductors. According to IEEE Spectrum, they consist of a CdSe inner core, a Cd1−xZnxS outer shell and a silica coating that prevents them from oxidation. The quantum dots are spead into a thin sheet that can be placed onto a glass window pane.

When photons from sunlight hit a quantum dot, it sends the electron in the valence band into the conduction band, leaving a hole behind. When the electron recombines with the hole in the valence band, a new photon with lower energy is generated.

This new photon propagates within the glass via internal reflections. Energy is then generated when the propagating photons reach the window frame, where solar cells are stored.

The coating of quantum dots can be used on any window and to turn it into a sunlight harvesters at costs lower than are currently available.

The study was published in Nature Energy on Oct 10.