Photoactive Materials Research Unit, IDONIAL Technology Center, 33417 Avilés, Asturias, Spain.
Int J Mol Sci. 2023 Feb 10;24(4):3602. doi: 10.3390/ijms24043602.
Artificial lighting is ubiquitous in modern society, with detrimental effects on sleep and health. The reason for this is that light is responsible not only for vision but also for non-visual functions, such as the regulation of the circadian system. To avoid circadian disruption, artificial lighting should be dynamic, changing throughout the day in a manner comparable to natural light in terms of both light intensity and associated color temperature. This is one of the main goals of human-centric lighting. Regarding the type of materials, the majority of white light-emitting diodes (WLEDs) make use of rare-earth photoluminescent materials; therefore, WLED development is at serious risk due to the explosive growth in demand for these materials and a monopoly on sources of supply. Photoluminescent organic compounds are a considerable and promising alternative. In this article, we present several WLEDs that were manufactured using a blue LED chip as the excitation source and two photoluminescent organic dyes (Coumarin 6 and Nile Red) embedded in flexible layers, which function as spectral converters in a multilayer remote phosphor arrangement. The correlated color temperature (CCT) values range from 2975 K to 6261 K, while light quality is preserved with chromatic reproduction index (CRI) values superior to 80. Our findings illustrate for the first time the enormous potential of organic materials for supporting human-centric lighting.
人工照明在现代社会中无处不在，但它对睡眠和健康有不利影响。其原因是，光不仅负责视觉，还负责非视觉功能，例如调节生物钟系统。为了避免生物钟紊乱，人工照明应该是动态的，在一天中不断变化，其光强度和相关色温的变化方式应与自然光相媲美。这是以人为中心的照明的主要目标之一。关于材料类型，大多数白色发光二极管 (WLED) 都使用稀土磷光材料；因此，由于对这些材料的需求呈爆炸式增长，以及供应来源的垄断，WLED 的发展面临严重风险。磷光有机化合物是一种相当有前途的替代材料。在本文中，我们展示了几种使用蓝色 LED 芯片作为激发源制造的 WLED，其中嵌入了两种灵活层中的磷光有机染料（香豆素 6 和尼罗红），它们作为多层远程荧光体排列中的光谱转换器。相关色温 (CCT) 值范围从 2975 K 到 6261 K，而显色指数 (CRI) 值高于 80，保持了良好的光质量。我们的研究结果首次表明，有机材料在支持以人为中心的照明方面具有巨大潜力。
