Department of Materials Science and Engineering, Hongik University, Seoul, South Korea.
Opt Lett. 2013 Aug 1;38(15):2885-8. doi: 10.1364/OL.38.002885.
Highly bright CuInS₂ quantum dots (QDs), whose emission is easily tuned in orange and greenish-yellow colors through manipulating the ZnS shelling procedure, are integrated with polymethyl methacrylate (PMMA) to obtain a free-standing composite plate of QD-polymer. The composite plate embedded with orange or greenish-yellow QDs is combined in a remote type with a blue light-emitting diode (LED). No color rendering index (CRI) value results when orange QDs are applied, whereas use of greenish-yellow QDs leads to a limited CRI of 72. A higher-color rendering QD-LED is demonstrated through a spectral extension by devising a unique bilayer-structured QD plate, where two types of QD are separately incorporated into each PMMA matrix, with a buffer layer of polymer blend inserted between them. The bilayered QD plate LED exhibits an improved CRI of 81, a high luminous efficacy of 71.2 lm/W at an input current of 20 mA, and exceptional high-stability luminescent characteristics against the variation of applied current.
高度明亮的 CuInS₂ 量子点（QD），其发射光可通过操纵 ZnS 壳层处理轻松调谐为橙色和绿黄色，与聚甲基丙烯酸甲酯（PMMA）集成，以获得 QD-聚合物的独立复合板。嵌入橙色或绿黄色 QD 的复合板以远程方式与蓝色发光二极管（LED）结合。使用橙色 QD 时不会产生显色指数（CRI）值，而使用绿黄色 QD 则导致 CRI 有限，为 72。通过设计独特的双层结构 QD 板进行光谱扩展，展示了一种高显色 QD-LED，其中两种类型的 QD 分别被纳入每个 PMMA 基质中，它们之间插入聚合物共混物的缓冲层。双层 QD 板 LED 具有改进的 CRI 81，在 20 mA 的输入电流下具有 71.2 lm/W 的高光效，并且在施加电流变化时具有出色的高稳定性发光特性。
