Concepedia

Colloidal CsPbBr<sub>3</sub> Perovskite Nanocrystals: Luminescence beyond Traditional Quantum Dots

Abhishek Swarnkar, Ramya Chulliyil, Vikash Kumar Ravi, Mir Irfanullah, Arindam Chowdhury, Angshuman Nag

Angewandte Chemie · 2015 · 391 citations · 35 references

TL;DR

Traditional CdSe‑based colloidal quantum dots exhibit notable photoluminescence properties. The study highlights the advantages of colloidal CsPbBr₃ nanocrystals in both ensemble and single‑nanocrystal photoluminescence over traditional cQDs. Colloidal CsPbBr₃ nanocrystals achieve ~90 % PL quantum yield with a narrow 86 meV FWHM, identical single‑ and ensemble spectral widths, minimal self‑absorption and FRET, ±1 nm reproducible peaks, temperature‑stable emission from 25–100 °C, and suppressed blinking with ~90 % of particles >85 % on‑time, outperforming traditional CdSe quantum dots.

Abstract

Abstract 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.