High-quality CsPbBr₃ perovskite nanocrystals for quantum dot light-emitting diodes

Abstract

We synthesized luminescent CsPbBr3 nanocrystals with a high quantum yield and realized patterning and color-purity light-emitting diode applications.

Light Generation in Lead Halide Perovskite Nanocrystals: LEDs, Color Converters, Lasers, and Other Applications

“…In both 2D and 3D LHP‐NCs, the corner‐sharing [PbX 6 ] 4− octahedron is the core fragment, and Pb 2+ always occupies the pivot site of an octahedron formed by halogen anions. This site also corresponds to the center of the cube formed by A‐cations in 3D LHPs …”

“…The energy level configuration of LHPs is mainly determined by the site‐B and site‐X components . The valence band for LHPs is hybridized by the np orbitals of the halogens and the 6s orbitals of lead, whereas the conductive band is mainly determined by the lead 6p orbitals with a minor contribution from the np orbitals of the halogens (Figure c) .…”

“…Thus, the bandgap of LHPs can be widely tuned by exchanging halogen species with different np orbital energy levels (Cl‐3p, Br‐4p, and I‐5p) . Changing the halogen species from chlorine to iodine drastically shifts the light emitted from the resulting LHPs from near‐ultraviolet to near‐infrared (Figure d) . Exploiting alloyed halide species at various ratios to occupy site‐X allows the flexible tuning of the bandgap of the resulting LHPs, resulting in continuously adjustable emissive spectra across the entire visible range (Figure d) .…”

“…Generally, LHP‐NCs can be represented in the form ABX 3 , where site‐A is an amine or cesium, site‐B is lead, and site‐X is a halogen . By varying the components, LHP‐NCs can exhibit independent properties with small deviations, including a high charge carrier mobility, excellent defect tolerance, efficient luminescence, and narrow emissive spectra that cover significantly different wavelengths from the near‐ultraviolet to the near‐infrared . As the use of LHP‐NCs in various applications has grown rapidly, environmental concerns about the use of toxic lead have emerged.…”

Silver nanoparticles enhanced luminescence and stability of CsPbBr3 perovskite quantum dots in borosilicate glass

“…There have been many routes to prepare this type of semiconductor material, including thermal injection, ligand‐assisted supersaturation recrystallization, a microwave‐assisted method, and an ion exchange method . Although perovskite quantum dots possess excellent optical properties, their poor stability limits their practical application.…”