Surface Passivation Strategies for Improving Photoluminescence and Stability of Cesium Lead Halide Perovskite Nanocrystals

Abstract

Cesium lead halide (CsPbX 3) perovskite nanocrystals (NCs) are of great interest for next-generation optoelectronics because of its excellent optical properties and exceptional colour tunability. Nevertheless, these materials suffer degradation which has become a major challenge for their use in practical applications. Researchers mainly focused on developing various approaches to improve the photoluminescence properties and stability of CsPbX 3 perovskite NCs. Among these, herein, we review some of the promising approaches to address the challenges like post-synthetic modification, ligand exchange, and in situ addition.

Cesium Lead Bromide Perovskite Nanocrystals as a Simple and Portable Spectrochemical Probe for Rapid Detection of Chlorides

“…[8,9[10]] Among which CsPbX 3 (X=Cl, Br, and I) perovskite NCs are of great interest because of their high photoluminescence quantum yield (PLQY), defect tolerance, and wide range band-gap tunability and ease of synthesis. [8,[11][12][13][14][15][16] The facile and instant anion-exchange process facilitated by cesium lead bromide (CsPbBr 3 ) perovskite nanocrystals (NCs) [17] persuaded the potential towards chloride detection. Taking the advantage of spectral tunability of these materials by varying the halide composition, one can access the presence of other halide materials based on the extent and rate of anion exchange.…”

“…On the other hand, metal halide perovskites have a growing interest because of their excellent optical properties. [8,9[10]] Among which CsPbX 3 (X=Cl, Br, and I) perovskite NCs are of great interest because of their high photoluminescence quantum yield (PLQY), defect tolerance, and wide range band‐gap tunability and ease of synthesis [8,11–16] . The facile and instant anion‐exchange process facilitated by cesium lead bromide (CsPbBr 3 ) perovskite nanocrystals (NCs) [17] persuaded the potential towards chloride detection.…”

Red-Emissive Nanocrystals of Cs4MnxCd1-xSb2Cl12 Layered Perovskite

“…22 This unfavorable effect, already documented in several metal-halide perovskites, can be ascribed to the formation of non-radiative relaxation paths induced by surface traps. To test this hypothesis, we attempted three different post-synthetic treatments to boost the PLQY of the nanocrystals: a small fraction of the nanocrystals suspension was added to i) a mixture of CdCl2, OA and OlAm in hexane; 29,31 ii) a solution of didodecyldimethylammonium chloride (DDAC) in toluene; 32 iii) a mixture of ammonium thiocyanate (NH4SCN) in hexane 33,34 (see Experimental parts). The first two treatments decomposed the samples, while the emission was successfully enhanced by NH4SCN.…”

Surface modification for improving the photoredox activity of CsPbBr3nanocrystals

“…Inorganic cesium lead halide perovskite nanocrystals (CsPbX3, X=I, Br, Cl) have been of great interest to researchers because of their very high photoluminescence quantum yield (~upto 90%), broad absorbance, and narrow emission with wide spectral tunability. [1][2][3][4][5][6] These materials are at the forefront of research due to their lowtemperature facile synthesis, tolerance to surface defects, and low exciton binding energies. 1,[7][8][9] Due to these excellent optoelectronic properties 1,[10][11][12][13] and facile synthesis the PNCs got great attention as active material in several optoelectronic devices such as lightemitting diodes, 14,15 solar cells, 16 photodetector, 17 scintillators 18 , and photocatalysis.…”