Deng Hao-Hua, Zhuang Qiong-Qiong, Huang Kai-Yuan, Balasubramanian Paramasivam, Lin Zhen, Peng Hua-Ping, Xia Xing-Hua, Chen Wei
Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China.
State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Nanoscale. 2020 Jul 30;12(29):15791-15799. doi: 10.1039/d0nr03640d.
As a new emerging candidate for solid-state phosphors, copper nanoclusters (CuNCs) have gained tremendous interest in the field of white light-emitting devices (WLEDs). However, their further applications are impeded by the low photoluminescence quantum yield (PLQY) and poor emission color tunability of CuNCs. This work demonstrates the synthesis of cyan and orange emitting CuNCs, and their combination as color conversion phosphors in WLEDs. The cyan and orange emitting CuNCs were prepared employing 2-mercapto-1-methylimidazole (MMI) and N-acetyl-l-cysteine (NAC), respectively, as stabilizing-cum-reducing agents. The dispersions of MMI-CuNCs and NAC-CuNCs are weakly emissive. However, after processing into powders, they both possess ultrahigh PLQYs (45.2% for MMI-CuNCs, and 64.6% for NAC-CuNCs) owing to the effect of aggregation-induced emission (AIE). All-CuNC based WLEDs are then designed and developed using powdered MMI-CuNC and NAC-CuNC samples on commercially available 365 nm GaN LED chips. They display acceptable white light characteristics with a Commission Internationale de l'Eclairage coordinate value and color rendering index of (0.26, 0.30) and 83, respectively. We believe that these cost-effective and eco-friendly CuNCs with interesting AIE properties will vigorously promote the development of high-quality WLEDs for commercial applications.
作为一种新兴的固态荧光粉候选材料，铜纳米团簇（CuNCs）在白光发光器件（WLEDs）领域引起了极大的关注。然而，它们的进一步应用受到CuNCs低光致发光量子产率（PLQY）和较差的发射颜色可调性的阻碍。这项工作展示了发射青色和橙色光的CuNCs的合成，以及它们作为WLEDs中的颜色转换荧光粉的组合。分别使用2-巯基-1-甲基咪唑（MMI）和N-乙酰-L-半胱氨酸（NAC）作为稳定兼还原剂制备了发射青色和橙色光的CuNCs。MMI-CuNCs和NAC-CuNCs的分散体发射较弱。然而，加工成粉末后，由于聚集诱导发光（AIE）效应，它们都具有超高的PLQY（MMI-CuNCs为45.2%，NAC-CuNCs为64.6%）。然后，使用市售365 nm GaN LED芯片上的粉末状MMI-CuNC和NAC-CuNC样品设计并开发了全CuNC基WLEDs。它们显示出可接受的白光特性，国际照明委员会坐标值和显色指数分别为（0.26，0.30）和83。我们相信，这些具有有趣AIE特性的经济高效且环保的CuNCs将有力地推动用于商业应用的高质量WLEDs的发展。
