Colloidal CsPbBr 3 Perovskite Nanocrystals: Luminescence beyond Traditional Quantum Dots

Traditional CdSe‐based colloidal quantum dots (cQDs) have interesting photoluminescence (PL) properties. Herein we highlight the advantages in both ensemble and single‐nanocrystal PL of colloidal CsPbBr 3 nanocrystals (NCs) over the traditional cQDs. An ensemble of colloidal CsPbBr 3 NCs (11 nm) exhibits ca. 90 % PL quantum yield with narrow (FWHM=86 meV) spectral width. Interestingly, the spectral width of a single‐NC and an ensemble are almost identical, ruling out the problem of size‐distribution in PL broadening. Eliminating this problem leads to a negligible influence of self‐absorption and Förster resonance energy transfer, along with batch‐to‐batch reproducibility of NCs exhibiting PL peaks within ±1 nm. Also, PL peak positions do not alter with measurement temperature in the range of 25 to 100 °C. Importantly, CsPbBr 3 NCs exhibit suppressed PL blinking with ca. 90 % of the individual NCs remain mostly emissive (on‐time >85 %), without much influence of excitation power.