Quantum dot solar power research. Researchers with solutions of perovskite quantum dots, showing intense photoluminescence when illuminated with ultraviolet (UV) light. CsPbBr3 emits in the green part of the spectrum and CsPbI3 emits in the red part of the spectrum. This work is being carried out at the National Renewable Energy Laboratory (NREL), Golden, Colorado, USA. The researchers here have set efficiency records for a quantum dot solar cell. Quantum dots are tiny nanoparticles that can be used to harness solar energy to produce electricity. Photographed in September 2016.