I-Corps: Stable and efficient organic light-emitting diodes (OLEDs) for applications in horticulture and architectural lighting

这个I-Corps项目的更广泛的影响/商业潜力是光源的潜在发展，可以改善室内植物和作物的生长，用于园艺应用，如室内垂直农业和水培。此外，提议的光源可以通过提供更自然的色彩光谱来增强建筑照明。传统的无机半导体发光二极管（LED）器件通常在可见光谱范围内不具有均匀的光谱强度。例如，用于照明目的的白光LED光源在光谱的绿色部分（称为“绿色间隙”）的发射强度会有明显的下降。因此，被这些LED光源照亮的物体不会显示出真实的颜色。另一方面，有机发光二极管（OLED）器件可以生产几乎任何发光颜色，在光谱的绿色和红色部分具有出色的强度和效率。oled具有包含有机或有机金属材料的发射层，而不是传统的无机化合物半导体。然而，oled的一个长期存在的问题是其蓝色发射成分，它不如红色和绿色稳定。此外，光提取效率约为20-50%，并且有很大的提高空间。提出的技术可以通过增加蓝色OLED发射的稳定性和通过改善可见光光谱的光提取来解决这两个问题。提出的技术可能会产生稳定的光源，基于可持续的，低工艺能量的有机半导体，其能源效率与传统的LED光源相当，但具有增强的光谱质量。这个I-Corps项目是基于提高有机发光二极管（OLED）光源的效率和稳定性的潜在技术发展。与传统的无机发光二极管（led）相比，oled具有更好的光谱质量；然而，它们的稳定性和效率还不是商业照明应用的最佳选择。所提出的技术可以解决oled发光的蓝色成分稳定性和效率低的问题。稳定的蓝光发射对于建筑和园艺照明都是必要的，之前的研究表明，与现有的蓝色oled相比，拟议的核心技术可能会将蓝色oled的稳定性提高3.6倍。此外，白色oled的效率还不够高，用于建筑和一些园艺照明应用，这些应用通常需要1,000 cd/m2。提出的技术可以通过增加光提取来提高OLED的效率，这可能有助于解决效率问题。纳米结构的等离子体电极可以增强可见电磁波波长的局部电场，并且可以根据纳米结构的大小和形状进行调谐。当等离子体波长与纳米结构附近发光材料的波长重叠时，可以提供更快、更稳定的发光。使用等离子体电极的纳米结构器件具有与典型平面金属电极相当的电学行为，但具有优越的光稳定性和光提取效率。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact/commercial potential of this I-Corps project is the potential development of light sources that may improve indoor plant and crop growth for horticulture applications such as indoor vertical farming and hydroponics. Additionally, the proposed light sources could enhance architectural lighting by providing a more natural spectrum of color. Conventional inorganic semiconductor-based light-emitting diode (LED) devices usually do not have uniform spectral intensity across the visible spectrum. For example, white-light LED light sources used for lighting purposes can have a significant dip in emission intensity in the green part of the spectrum (called the “green gap”). Hence, objects illuminated by these LED lighting sources do not show true colors. Organic light-emitting diode (OLED) devices, on the other hand, can be produced with virtually any emission color with excellent intensity and efficiency in the green and red parts of the spectrum. OLEDs have an emitting layer containing an organic or organometallic material instead of conventional inorganic compound semiconductors. However, one persistent issue with OLEDs is in their blue emission component, which is less stable than red and green. Furthermore, light extraction efficiencies are ~20-50% and have substantial room for improvement. The proposed technology may address both issues by increasing the stability of blue OLED emission and by improved light extract across the visible spectrum. The proposed technology may produce stable light sources based on sustainable, low-process-energy organic semiconductors that have energy efficiencies comparable to traditional LED light sources, but with enhanced spectral qualities.This I-Corps project is based on the potential development of technology to improve the efficiency and stability of organic light-emitting diode (OLED) light sources. OLEDs have improved spectral qualities compared to more traditional inorganic light-emitting diodes (LEDs); however, their stability and efficiency are not yet optimal for commercial lighting applications. The proposed technology may address the low stability and efficiency of the blue component of light emission from OLEDs. Stable blue emission is necessary for both architectural and horticulture lighting and previous research indicates that the proposed core technology may increase the stability of blue OLEDs by a factor of up to 3.6 compared to existing blue OLEDs. Additionally, the efficiency of white OLEDs is not yet high enough for architectural and some horticulture lighting applications where 1,000 cd/m2 are required routinely. The proposed technology could improve OLED efficiency by increasing light extraction, which may help address the efficiency problem. Nanostructured plasmonic electrodes were designed that enhance the local electric fields at visible electromagnetic wavelengths and may be tuned depending upon the size and shape of the nanostructures. When the plasmon wavelength overlaps with the wavelength of the light-emitting materials in the close vicinity of nanostructures, it may provide faster and more stable light emission. The proposed nanostructured devices using plasmonic electrodes could have comparable electrical behavior to the typical planar metal electrodes but show superior photostability and light extraction efficiency.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.