Luminescent Organometallic Complexes with Fast Radiative Rates

具有快速辐射速率的发光有机金属配合物

• 批准号: 2348784
• 负责人: Thomas Teets
• 金额: $ 47.12万
• 依托单位: University of Houston
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-06-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2348784&HistoricalAwards=false
• 关键词: Luminescent; Organometallic; Complexes; Fast; Radiative

WIth support from the Chemical Structure, Dynamics & Mechanisms-B (CSDM-B) Program of the Chemistry Division, Thomas Teets of the Department of Chemistry at University of Houston is investigating strategies to increase the radiative decay rates in phosphorescent metal complexes. Phosphorescent metal complexes have been used in a variety of optoelectronic applications, most notably organic light-emitting diodes (OLEDs), a lighting technology that is widely used in color displays and other consumer products. The goal of this project is to use complementary molecular design strategies in a few different classes of phosphorescent compounds to increase their radiative rates, with long-term implications of producing OLEDs with improved efficiency and durability. The work combines innovative synthetic chemistry to make new molecules and in-depth photophysical characterization to measure the color profile, efficiency, and timescale of light emission. Standing at the interface of organometallic chemistry and photochemistry, this research aims to produce insightful structure-property relationships that lead to the discovery of top-performing phosphorescent metal complexes. Another part of this project will develop a publicly available web database of photochemically active compounds, allowing researchers at all levels to search and sort the database for compounds that have specific properties of interest. Finally, this research project will serve as a training ground for undergraduate and graduate researchers in experimental physical inorganic chemistry research to contribute to the future science and technology workforce.Under this award, the Tests research team will pursues three complementary strategies for increasing the radiative rates and photoluminescence quantum yields of organometallic phosphors. The first two focus on blue phosphorescence, which remains one of the most significant technical challenges in the optoelectronic field. Platinum acetylide compounds are a promising class of blue-phosphorescent compounds, but their slow radiative rates have hindered their widespread deployment in OLEDs. This project will introduce the “secondary heavy-metal effect” as a strategy to increase radiative rates, by decorating the periphery of platinum aryl acetylide compounds with other heavy metals. These approaches center on pyridyl-substituted acetylides which can coordinate to a variety of heavy metal additives, binding of coinage metals directly to the acetylide π-electrons, and covalent gold-carbon bond formation on the aryl acetylide ligands. Although organoplatinum complexes are the major focus of this work, a second strategy for blue phosphorescence with fast radiative rates will involve a new class of cyclometalated iridium acetylide compounds. These compounds will combine the advantageous sharp blue phosphorescence originating from aryl acetylides with the inherently larger spin-orbit coupling and faster radiative rates that iridium engenders. Finally, the last major thrust of this project centers on cyclometalated platinum complexes, with an emphasis on luminescence in the lower-energy regions (red to near-infrared) of the spectrum. These compounds will feature electron-rich ancillary ligands that can stabilize charge-transfer states, increase excited-state spin-orbit coupling, and augment radiative rate constants. Steric effects on both the cyclometalating and ancillary ligand will also be investigated and are important for minimizing aggregation and suppressing nonradiative rates.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.

在化学系化学结构、动力学和机理-B (CSDM-B) 项目的支持下，休斯顿大学化学系的 Thomas Teets 正在研究提高磷光金属配合物的辐射衰变率的策略。配合物已用于各种光电应用，最引人注目的是有机发光二极管（OLED），这是一种广泛用于彩色显示器和其他消费者的照明技术该项目的目标是在几种不同类别的磷光化合物中使用互补的分子设计策略来提高其辐射率，从而提高生产效率和耐用性的 OLED。这项研究站在有机金属化学和光化学的交叉点，旨在通过新分子和深入的光物理表征来测量光发射的颜色分布、效率和时间尺度，旨在产生富有洞察力的结构-性质关系，从而发现光发射。该项目的另一部分将开发一个公开的光化学活性化合物网络数据库，使各级研究人员能够搜索和排序具有特定性能的化合物的数据库。作为实验物理无机化学研究的本科生和研究生研究人员的培训基地，为未来的科学和技术劳动力做出贡献。根据该奖项，测试研究团队将采取三种互补策略，以提高辐射率和光致发光量子产率前两种主要关注蓝色磷光，这仍然是光电领域最重大的技术挑战之一。乙炔铂化合物是一类很有前途的蓝色磷光化合物，但其缓慢的辐射速率阻碍了其在 OLED 中的广泛应用。该项目将通过装饰芳基乙炔铂化合物的外围引入“二次重金属效应”作为提高辐射率的策略。这些方法以吡啶基取代的乙炔化物为中心，它可以与多种重金属添加剂配位，将造币金属直接与乙炔化物π电子结合，并在芳基有机铂配体上形成共价金-碳键。配合物是这项工作的主要焦点，具有快速辐射速率的蓝色磷光的第二种策略将涉及一类新的环金属化这些化合物将源自芳基乙炔的有利的锐蓝色磷光与铱产生的固有的更大的自旋轨道耦合和更快的辐射速率结合起来。这些化合物的重点是光谱中低能区域（红色至近红外）的发光，具有富含电子的辅助配体。稳定电荷转移态、增加激发态自旋轨道耦合以及增强环金属化和辅助配体的空间效应也将得到研究，这对于最大限度地减少聚集和抑制非辐射速率非常重要。该奖项反映了 NSF 的法定规定。使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。