Hydroxyl-Terminated CuInS2 Based Quantum Dots: Toward Efficient and Bright Light Emitting Diodes
Hydroxyl-Terminated CuInS2 Based Quantum Dots: Toward Efficient and Bright Light Emitting Diodes
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羟基封端的 CuInS2 基量子点：迈向高效、明亮的发光二极管
DOI：
10.1021/acs.chemmater.5b04480
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发表时间：
2016-02-23
影响因子：
8.6
通讯作者：
Zhong, Haizheng
中科院分区：
文献类型：
--
作者：
Bai, Zelong;Ji, Wenyu;Zhong, Haizheng
基于Cuins2的量子点由于其宽阔和可调的排放以及大量的Stokes变化而成为新一代白色照明技术的低毒材料。在这里，我们开发了一种简单的原位配体交换策略，用于制造基于6-甲基己醇的基于羟基终止Cuins2的量子点。在配体交换过程中，量子点表面上的长链甲基末端的油胺可以有效，有效地被短链羟基羟基终止的6-甲基己醇替代，从而在极性有机溶剂中溶解性，例如Ass-Organic Solvents，如甲醇，乙醇，乙醇和乙醇，乙醇和乙醇，乙醇，乙醇和乙醇二甲基甲酰胺。此外，所得的羟基终止量子点具有保存完好的光致发光特性，其量子产率与70％相似。使用这些基于羟基端的Cuins2量子点作为发射层，我们通过采用倒置的设备结构来制造有效且明亮的发光二极管。优化的设备的最大亮度为8,735 cd/m（2），外部量子效率为3.22％。此外，可以通过考虑电子传输层和发射层之间的能量屏障的减少来解释性能增强。高效效率和增强的亮度以及使用绿色溶剂的潜在全解决加工性的结合使用6-甲基己醇封闭的羟基终止的量子点成为了新一代的材料，用于发光应用。
CuInS2 based quantum dots are emerging as low toxic materials for new generation white lighting technology due to their broad and color-tunable emissions as well as large Stokes shifts. Here, we developed a simple and in situ ligand exchange strategy for the fabrication of hydroxyl terminated CuInS2 based quantum dots capped with 6-mercaptohexanol. During the ligand exchange, long-chain methyl-terminated oleylamine on the quantum dots' surface can be effectively and efficiently replaced by the short-chain hydroxyl-terminated 6-mercaptohexanol, enabling their solubility in polar organic solvents such as methanol, ethanol, and dimethylformamide. Moreover, the resulting hydroxyl-terminated quantum dots exhibit well-preserved photoluminescence properties with quantum yields of similar to 70%. Using these hydroxyl-terminated CuInS2 based quantum dots as an emitting layer, we fabricated efficient and bright light emitting diodes by adopting an inverted device structure. The optimized devices show a maximum luminance of 8,735 cd/m(2) and an external quantum efficiency of 3.22%. Furthermore, the performance enhancement can be explained by considering the decreased energy barriers between the electron transport layer and the emitting layer. The combination of high efficiency and enhanced brightness as well as the potential all-solution processability using green solvents makes hydroxyl-terminated quantum dots capped with 6-mercaptohexanol a new generation of materials for light emitting applications.