Different from the narrow band emission based on free excitons in lead-perovskite nanocrystals (NCs), the low electronic dimensionality in lead-free double perovskite NCs can lead to self-trapped excitons (STEs), generating a broadband emission.
Click here for original story, Synthesizing double perovskite nanocrystals with bright emission based on triplet self-trapped excitons
Source: Phys.org