Cathodoluminescence spectral and lifetime mapping of Cs4PbBr6: fast lifetime and its scintillator application

Highly efficient green emission of Cs _4 PbBr _6 has been attributed to intermediate states formed by embedded CsPbBr _3 nanocrystals or defects. However, direct experimental confirmation of the presence of such nano-emitters is not straightforward and the emission mechanism remains elusive. By using cathodoluminescence (CL) imaging with a high spatial resolution, we demonstrate that CsPbBr _3 nanocrystals within the Cs _4 PbBr _6 matrix contribute to the green emission, exhibiting optical behavior distinct from the matrix. Additionally, we explore its potential as an electron beam scintillator, given its high CL intensity and exceptionally short lifetime.