Stable and highly efficient blue-emitting CsPbBr3 perovskite nanomaterials via kinetic-controlled growth

Facile synthesis of Mn2+ doped ultrathin (n = 2) NPLs and their application in anti-counterfeiting

“…Hence, this new green emitting peak at 517 nm is due to the further growth of the existing NPLs. Because of the strong electronic affinity between Ag + and Br − and the ionic nature of perovskite, AgBr can be easily formed and coated onto the surface of perovskite, 4,20,51 resulting in enhanced stability.…”

“…Metal halide perovskite materials as one of the hottest semiconducting materials have attracted great interest in applications such as solar cells, photodetectors, light-emitting diodes (LEDs) and lasers due to their fascinating properties including high absorption cross-sections, tunable bandgaps, high photoluminescence quantum yield (PLQY). [1][2][3][4][5][6][7][8][9][10][11][12] Recently, most studies on perovskites have focused on the colloidal perovskite nanomaterials because of the strong quantum confinement effect, good stability over the bulk materials and solution processability. 2,[13][14][15][16][17][18][19][20][21] Compared with 3D perovskite nanocrystals (NCs), 2D perovskite nanoplatelets (NPLs) with thicknesses at the atomic scale have many distinct optical properties including narrow absorption and emission spectra, large exciton binding energies and high absorption crosssections.…”

“…2,[13][14][15][16][17][18][19][20][21] Compared with 3D perovskite nanocrystals (NCs), 2D perovskite nanoplatelets (NPLs) with thicknesses at the atomic scale have many distinct optical properties including narrow absorption and emission spectra, large exciton binding energies and high absorption crosssections. 4,20,[22][23][24][25][26] These exceptional optical properties are beneficial for application in LEDs and lasers, which is hard to achieve and strongly required in colloidal NCs. 27 2D NPLs can be prepared according to the experience gained through the synthesis of CsPbX 3 NCs.…”

Slowing Down for Growth Mechanism and Speeding Up for Performance Optimization Based on Single Ligand Passivated CsPbBr3 Nanoplatelets

“…[11] Su et al have slowed down the reaction rate by adding additional Ag + to control the release rate of Br -. [4] The PLQY of products synthesized under relatively fast reaction rate is only 40%, while it reaches 98% after the deceleration of additional Ag + . In fact, one would prefer to get high PLQY of the products via a rapid reaction process to reduce the time cost.…”

“…Besides the structural optimizing of devices, designing stable and bright pure blue emissive MHPs via a simple and effective method is still a key part for improving the final EQE values.Three typical strategies for pure blue emissive perovskites are available: composition engineering (e.g., Br-Cl hybridization), quantum confinement strategy (e.g., synthesis of small size Br-based quantum dots), and dimensional engineering (e.g., quasi-two dimension Br-based nanoplatelets (NPls)). [4] Among them, composition engineering through Br-Cl hybridization may cause unavoidable phase segregation under photo-excitation or electrical bias, leading to redshift or multiple emissions in photoluminescence emission (PL) spectrum. [5] Quantum confinement strategy for Br-based perovskites nanocrystals is widely accepted for blue emitters because of its higher defect tolerance compared with Cl-or Br/ Cl-based MHPs.…”