Optoelectronic Applications of Thermally Activated Delayed Fluorescence

热激活延迟荧光(TADF)的发现引发了发光材料科学与工程领域的一场革命。这些材料可以在下一代显示器和光源中高效地收集能量，并成为当今使用的最先进的有机发光二极管(OLED)的基础。全球OLED市场在2021年达到384亿美元，预计在未来五年内将翻一番，因为TADF技术使手机、电视和灯具具有更鲜艳的色彩、更长的电池寿命和更高的对比度。这种范式的转变让我们提出了一个问题，这个问题现在激励了我们的大部分研究计划：TADF材料能否在其他使用荧光材料的领域创造出类似的颠覆性技术？该提案旨在将TADF技术应用于荧光材料研究的三个关键领域。首先，我们将开发用于荧光成像和跟踪疾病细胞的发光纳米颗粒。使用TADF，我们将开发出从生物细胞和组织中过滤出荧光背景信号的探测器，提供更高分辨率的细胞和细胞结构图像。其次，我们将使用TADF材料作为光催化剂，使我们能够用光加速化学反应。与传统的荧光材料不同，TADF材料可以将来自光能的能量存储在电子中更长时间，使其有时间将这些能量传递给其他分子。通过这种方式，TADF材料起到光催化剂的作用，可以用来合成聚合物、药物或其他传统方法难以获得的先进材料。最后，我们将研究TADF材料在有机长余辉发光(OLPL)和三重-三重湮没上转换(TTA-UC)材料中的新应用。OLPL材料储存能量并在几分钟到几小时内发光，可能会取代传统的无机暗发光化合物，这些化合物需要稀土元素和较高的制造温度。TTA-UC材料可以将低能量吸收的光转换为高能荧光，非常适合于生物应用，其中红色吸收的光可以用来穿透组织，蓝色发射的光可以用于治疗。总体而言，这项提议旨在释放TADF材料在OLED以外的应用中的潜力，利用发光材料创造颠覆性技术。

The discovery of thermally activated delayed fluorescence (TADF) has sparked a revolution in the science and engineering of luminescent materials. These materials allow for efficient harvesting of energy in next-generation displays and light sources, and underlie the most advanced organic light-emitting diodes (OLEDs) in use today. The global OLED market reached $38.4B USD in 2021, and is expected to nearly double in the next five years as TADF technology enables cellphones, televisions, and light fixtures with more vibrant colours, longer battery lives and higher contrast. This paradigm shift led us to the question that now motivates much of our research program: Can TADF materials be used to create similarly disruptive technologies in other fields where fluorescent materials are used? This proposal aims to apply TADF technology to three key areas of fluorescent materials research. First, we will develop luminescent nanoparticles for fluorescent imaging and tracking of diseased cells. Using TADF, we will develop probes that filter out the fluorescent background signal from biological cells and tissues, giving higher-resolution images of cells and cell structures. Second, we will use TADF materials as photocatalysts, allowing us to accelerate chemical reactions using light. Unlike conventional fluorescent materials, a TADF material can store the energy from light in its electrons for longer, giving it time to pass that energy on to other molecules. In this way, the TADF material acts as a photocatalyst, and can be used to synthesize polymers, pharmaceuticals, or other advanced materials that are difficult to access by traditional means. Finally, we will investigate emerging applications of TADF materials in organic long-persistent luminescent (OLPL) and triplet-triplet annihilation upconversion (TTA-UC) materials. OLPL materials store energy and emit light over minutes to hours, and may offer a replacement to conventional inorganic glow-in-the-dark compounds that require rare earth elements and high fabrication temperatures. TTA-UC materials can convert low-energy absorbed light into high-energy fluorescence, ideal for biological applications where red absorbed light can be used to penetrate tissues, and blue emitted light can be used for therapy. Overall, this proposal aims to unlock the potential of TADF materials in applications beyond OLEDs, creating disruptive technologies from light-emitting materials.