High Water Resistance of Monoclinic CsPbBr₃ Nanocrystals Derived from Zero-Dimensional Cesium Lead Halide Perovskites

Abstract

An all-inorganic cesium lead halide perovskite is particularly attractive as an alternative to next-generation display with high quantum yields and color purity for lasers, light-emitting diode (LED) devices, and single-photon sources. Unfortunately, the vulnerable properties induced by moisture limit the hopeful application of CsPbBr 3 , especially for high-performance devices. In this work, a monoclinic CsPbBr 3 derived from hexagonal Cs 4 PbBr 6 with the assistance of water was presented. Moisture-induced decomposition and phase segregation were recorded at the atomic level in detail. Moreover, the obtained monoclinic CsPbBr 3 nanocrystals (NCs) are demonstrated to be decorated with hydroxyl (OH) ligands, which provide a valid approach for the resistance to further moisture attack. The highly stable CsPbBr 3 NCs could preserve the photoluminescence intensity above 97% even after the sample was deposited in water for 30 days. Furthermore, a white LED constructed with the as-prepared green-emitting CsPbBr 3 and a commercial N628 red phosphor demonstrate the monoclinic CsPbBr 3 as a compelling material platform well suited to applications as next-generation light emitters.

Transforming colloidal Cs4PbBr6 nanocrystals with poly(maleic anhydride-alt-1-octadecene) into stable CsPbBr3 perovskite emitters through intermediate heterostructures

“…[1][2][3] The chemical reactivity of these NCs and the interconversion between the NCs of the two most studied bromides in this class, Cs 4 PbBr 6 and CsPbBr 3 perovskite, have been of interest since these NCs were rst synthesized in the colloidal form. [4][5][6][7][8] The Cs 4 PbBr 6 / CsPbBr 3 conversion, which can be triggered using various reagents (for example, Prussian blue, 9 oleic acid, 10 PbBr 2 , 7,11 and water) [12][13][14] is an interesting approach to prepare emissive CsPbBr 3 NCs. For example, Yin's group exploited heterogeneous water-mediated CsBr extraction from Cs 4 PbBr 6 NCs in hexane as a method for making luminescent CsPbBr 3 /SiO 2 or CsPbBr 3 /Ta 2 O 5 Janus-type heterostructures, 13 and branched CsPbBr 3 dodecapods.…”

Low‐Dimensional‐Networked Cesium Lead Halide Perovskites: Properties, Fabrication, and Applications

“…An additional advantage of the resulting CsPbX 3 NCs was their higher stability against moisture due to the passivated surface, unlike those obtained through the hot-injection method. [26,151] This CsX-stripping by water provided a way to synthesize different CsPbX 3 based structures that were not producible by direct synthesis. [127] For example, monodisperse CsPbBr 3 nanorods (Figure 12e) with tunable aspect ratio have been obtained using Cs 4 PbBr 6 NCs as the starting material.…”

Aqueous Phase Exfoliating Quasi‐2D CsPbBr3 Nanosheets with Ultrahigh Intrinsic Water Stability

“…By analyzing the FTIR, the inherent differences between quasi‐2D CsPbBr 3 NSs and CsPbBr 3 QDs are the increase of OH groups and the decrease of OA and OAm. There the OH group may replace OA and OAm as the surface ligand and enhance the stability of quasi‐2D CsPbBr 3 NSs . In other hand, the enhancement of formation energy and inhibition of ions migration in 2D perovskite materials may also help maintenance of quasi‐2D CsPbBr 3 NSs.…”