清华大学张昊团队报道了用电子优化的重氮交联剂直接胶体量子点光图案化。相关研究成果发表在2024年10月9日出版的《美国化学会杂志》。

具有宽色域和高发光效率的胶体量子点（QDs）有望用于下一代电子和光子器件。然而，在不降低量子点性能的情况下，对量子点进行精确和可扩展的图案化，并将其集成到商业相关设备中，如数字可寻址量子点发光二极管（QLEDs）显示器，仍然具有挑战性。

该文中，研究人员开发了基于电子优化的二氮嗪交联剂，用于量子点的无损、直接光图案化，并最终构建有源矩阵QLED显示器。交联剂设计的关键是引入供电子取代基，形成基态单线态卡宾，用于空气稳定和良性的量子点光图案化。

在环境条件下，这些交联剂能够使用商业i线光刻技术，以每英寸超过13000像素的分辨率对无重金属的量子点进行图案化。图案化的量子点层完全保留了它们的光学和光电性能。

具有图案化InP/ZnSe/ZnS QD层的像素化电致发光器件，显示出15.3%的峰值外部量子效率和约40000 cd m^-2的最大亮度，优于现有QD图案化方法制造的器件。研究人员进一步展示了图案化QLEDs与薄膜晶体管电路的无缝集成，以及双色有源矩阵显示器的制造。这些结果强调了设计用于QD图案化的光化学的重要性，并显示可以在制造商业QLED显示器和其他集成QD器件平台时实施直接光图案化方法。

附：英文原文

Title: Direct Photopatterning of Colloidal Quantum Dots with Electronically Optimized Diazirine Cross-Linkers

Author: Zhong Fu, Stefania F. Musolino, Wenyue Qing, Hongjin Li, Felix J. de Zwart, Zhi Zheng, Mingfeng Cai, Yun Gao, Bas de Bruin, Xingliang Dai, Jeremy E. Wulff, Hao Zhang

Issue&Volume: October 9, 2024

Abstract: Colloidal quantum dots (QDs) with a wide color gamut and high luminescent efficiency are promising for next-generation electronic and photonic devices. However, precise and scalable patterning of QDs without degrading their properties and their integration into commercially relevant devices, such as digitally addressable QD light-emitting diode (QLED) displays, remain challenging. Here, we develop electronically optimized diazirine-based cross-linkers for nondestructive, direct photopatterning of QDs and, ultimately, building the active-matrix QLED displays. The key to the cross-linker design is the introduction of electron-donating substituents that permit the formation of ground-state singlet carbenes for air-stable and benign QD photopatterning. Under ambient conditions, these cross-linkers enable the patterning of heavy metal-free QDs at a resolution of over 13,000 pixels per inch using commercial i-line photolithography. The patterned QD layers fully preserved their optical and optoelectronic properties. Pixelated electroluminescent devices with patterned InP/ZnSe/ZnS QD layers show a peak external quantum efficiency of 15.3% and a maximum luminance of about 40,000 cd m–2, outperforming those made by existing QD patterning approaches. We further show the seamless integration of patterned QLEDs with thin-film transistor circuits and the fabrication of dual-color active-matrix displays. These results underscore the importance of designing photochemistry for QD patterning, and promise the implementation of direct photopatterning methods in manufacturing commercial QLED displays and other integrated QD device platforms.

DOI: 10.1021/jacs.4c09209

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c09209