School of Physical Science and Technology, ShanghaiTech University , 100 Haike Road, Shanghai 201210, China.
J Am Chem Soc. 2018 Jan 17;140(2):562-565. doi: 10.1021/jacs.7b10647. Epub 2018 Jan 2.
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 CsPbI 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/m luminance, surpassing by far LEDs made from the nonpassivated NCs.
虽然卤化物钙钛矿纳米晶体（NCs）是用于光电设备的有前途的材料，但它们严重受到化学和相不稳定性的影响。此外，封装 NCs 的常见封端配体，如油酸和油胺，将形成绝缘层，妨碍它们在光电设备中的应用。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 CsPbI NCs 的后合成钝化工艺。我们的钝化 NCs 表现出窄的红色光致发光，具有出色的量子产率（接近 1）和大大提高的稳定性。钝化 NCs 使我们能够实现红光发光二极管（LED），其外量子效率为 5.02%，亮度为 748 cd/m，远远超过了由非钝化 NCs 制成的 LED。
