Qu Dan, Yang Dongxue, Sun Yukun, Wang Xiayan, Sun Zaicheng
Center of Excellence for Environmental Safety and Biological Effects, Beijing Key Laboratory of Green Catalysis and Separation, Department of Chemistry and Chemical Engineering, School of Environmental and Energy , Beijing University of Technology 100 Pingleyuan , Chaoyang District, Beijing 100124 , People's Republic of China.
J Phys Chem Lett. 2019 Jul 18;10(14):3849-3857. doi: 10.1021/acs.jpclett.9b01575. Epub 2019 Jun 27.
Carbon dots (CDs) have been demonstrated to be fluorescent materials for the new phosphor-free white light-emitting diodes (WLEDs). Herein, we synthesized a novel white CDs (WCDs). The spectrum highly matches the solar light spectrum (AM 1.5), which is a potentially high-color-quality lighting source material. The CDs contain blue, green, and red emissive centers produced from catechol, -phenylenediamine, and their complexes, respectively. In addition, the photoluminescence mechanism had been revealed; three emission centers could be excited by a single UV source actuated by the formation of H- and J-aggregates and FRET between the CDs. Then the phosphor-free WLEDs were fabricated with a UV chip encapsulated with silicon resin containing the as-obtained CDs, which exhibit CIE coordinates of (0.33,0.33), a color rendering index (CRI) of 93, and a correlated color temperature (CCT) of 5453 K. The WLEDs show super stability and a high solar spectrum matching degree of 85-114%, protecting the eyesight. This provides a new way to design healthy lighting materials.
碳点（CDs）已被证明是用于新型无磷白色发光二极管（WLEDs）的荧光材料。在此，我们合成了一种新型白色碳点（WCDs）。其光谱与太阳光光谱（AM 1.5）高度匹配，是一种具有潜在高色质的照明源材料。这些碳点分别包含由儿茶酚、对苯二胺及其配合物产生的蓝色、绿色和红色发射中心。此外，光致发光机制已被揭示；通过碳点之间形成H-和J-聚集体以及荧光共振能量转移（FRET），单个紫外光源可以激发三个发射中心。然后，用含有所得碳点的硅树脂封装紫外芯片制备了无磷WLEDs，其CIE坐标为（0.33,0.33），显色指数（CRI）为93，相关色温（CCT）为5453K。这些WLEDs表现出超强稳定性和85 - 114%的高太阳光谱匹配度，可保护视力。这为设计健康照明材料提供了一种新方法。
