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Aggregation-Induced Emission Luminogens Sensitized Quasi-2D Hybrid Perovskites with Unique Photoluminescence and High Stability for Fabricating White Light-Emitting Diodes.

ABSTRACT: In order to endow quasi-2D organic-inorganic hybrid metal halide perovskites (quasi-2D-PVK) with superior performance, an aromatic organic ligand with aggregation-induced emission (AIE) features is rationally designed and utilized for constructing distinctive quasi-2D-PVK materials. This AIE-active ligand, TTPy-NH₂ , well fits into the lattices of quasi-2D-PVK and leaves hydrophobic tails surrounding PVK layers, making the presented TTPy-NH₂ /PVK film extraordinary in terms of both luminescence and stability. Benefiting from the prominent sensitization function and AIE tendency of TTPy-NH₂ , the presented TTPy-NH₂ /PVK film exhibits a high quantum yield of 62.2%, unique blue-red dual-emission property of both blue and red, high stability with the remnant of more than 94% fluorescence intensity remnant after 21 days. As a result, TTPy-NH₂ /PVK film is capable of constituting high-performance white light-emitting diodes, with its color gamut reaching 138% of the National Television System Committee （NTSC） standard and the maximum efficiency is 105 lm W^-1 at 20 mA. Evidently, a win-win effect is achieved by the integration of AIE-active ligands and quasi-2D-PVK, which are two of the most reputable solid-state luminogens. This developed protocol thus opens up a new avenue for exploring the next generation of luminescent devices.

SUBMITTER: Wang Y

PROVIDER: S-EPMC8336619 | biostudies-literature |

REPOSITORIES: biostudies-literature

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