High Optical Performance of Cyan‐Emissive CsPbBr₃ Perovskite Quantum Dots Embedded in Molecular Organogels

Abstract

Perovskite quantum dots (PQDs) have fascinating optoelectronic properties, such as high photoluminescence quantum yield (PLQY) for a broad range of materials, and the possibility to obtain different bandgaps with the same material or halide combinations. Nevertheless, blue‐emissive materials generally present limited PLQY or color instability. Here, two molecular organogels, based on a derivative of an amino acid and succinic acid, are used to embed CsPbBr3 quantum dots, obtaining green and blue emission. Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) measurements are performed to confirm that there are no significant changes in the average size of the QDs and the crystal structure. A high near‐unity PLQY is achieved for the blue emission. This contribution opens the door to a postsynthetic treatment for synthesizing blue‐emissive PQDs with high optical performance, which can be attractive for optoelectronic applications.

Zwitterionic Carbazole Ligands Enhance the Stability and Performance of Perovskite Nanocrystals in Light-Emitting Diodes

“…By X-ray photoelectron spectroscopy (XPS), we exclude the presence of chloride contamination in pure DCzGPC as a potential reason for the hypsochromic shift (Figure S7). We note that a concentration-dependent hypsochromic shift after addition of different bidentate ligands was also observed by other groups. − However, in those cases, the NC size shrunk during ligand exchange such that the shift was explained in terms of increased quantum confinement. In the present case, we observe the opposite, i.e., a slight increase in the NC size, which rules out increased quantum confinement as an explanation for the blue shift.…”

High Quality Inkjet Printed‐Emissive Nanocrystalline Perovskite CsPbBr3 Layers for Color Conversion Layer and LEDs Applications

“…[ 70 ] In this way, intra‐bandgap energy levels emerge into the big particles, favoring the non‐radiative recombination mechanism, and blocking the radiative channel. [ 71 ] In the case of films treated with HPl and CO, the presence of Cs + defects observed through XPS analysis could be reason to quench their characteristic PL features. However, as we discussed above, annealing treatment supports the preparation of PeQDs films with low density of pinholes/printing errors.…”

Direct in situ photolithography of ultra-stable CsPbBr3 quantum dot arrays based on crosslinking polymerization

“…The peaks located at 1644 cm −1 , 1588 cm −1 , and 1467 cm −1 correspond to the stretching vibration of the CvO bond, the bending vibration of the N-H bond, and the stretching vibration of the C-H bond, respectively. 24 Comparatively, the peak observed at 1154 cm −1 in the FTIR spectrum of the XBPO-treated PQDs is ascribed to the PvO stretching vibration, indicating that XBPO binds to the surface of PQDs. 25 This is consistent with the prominent 31 P NMR signal in the 1 H NMR spectrum of the XBPO-treated PQDs (ESI Fig.…”