Colloidal syntheses of zero-dimensional Cs4SnX6 (X = Br, I) nanocrystals with high emission efficiencies

The phase-pure all-inorganic zero-dimensional (0D) tin halides Cs4SnX6 (X = Br, I) nanocrystals (NCs) are successfully prepared for the first time. The as-prepared Cs4SnBr6 NCs exhibit a strongly Stokes-shifted broadband emission with a record-high photoluminescence quantum yield (PLQY) of 21 % at room temperature.