Although halide perovskite nanocrystals (NCs) are promising materials for optoelectronic devices, they suffer severely from chemical and phase instabilities. Moreover, the common capping ligands like oleic acid and oleylamine that encapsulate the NCs will form an insulating layer, precluding their utility in optoelectronic devices. To overcome these limitations, we develop a postsynthesis passivation process for CsPbI3 NCs by using a bidentate ligand, namely 2,2'-iminodibenzoic acid. Our passivated NCs exhibit narrow red photoluminescence with exceptional quantum yield (close to unity) and substantially improved stability. The passivated NCs enabled us to realize red light-emitting diodes (LEDs) with 5.02% external quantum efficiency and 748 cd/m2 luminance, surpassing by far LEDs made from the nonpassivated NCs.

中文翻译：

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双齿配体钝化的 CsPbI3 钙钛矿纳米晶体用于稳定的近统一光致发光量子产率和高效的红光发光二极管

尽管卤化物钙钛矿纳米晶体（NCs）是用于光电器件的有前途的材料，但它们受到化学和相不稳定性的严重影响。此外，封装NCs的常见封端配体如油酸和油胺将形成绝缘层，排除它们在光电器件中的应用。为了克服这些限制，我们通过使用双齿配体（即 2,2'-亚氨基二苯甲酸）开发了 CsPbI3 NCs 的合成后钝化工艺。我们的钝化 NC 表现出窄的红色光致发光，具有出色的量子产率（接近统一）和显着提高的稳定性。钝化的 NC 使我们能够实现具有 5.02% 外部量子效率和 748 cd/m2 亮度的红色发光二极管 (LED)，远远超过由非钝化 NC 制成的 LED。