通过精确控制激发状态能量水平来实现高效的热激活红色延迟光发射器
BoHua Zhang1, SiQi Liu1, JiangXue Pei1
1School of Chemistry, Xi'an Jiaotong University Xi'an 710049 P. R. China ddwang@mail.xjtu.edu.cn.
Chemical science
|April 19, 2024
概括
研究人员通过修改分子结构开发了具有热激活延迟光 (TADF) 的新红/近红外 (NIR) 材料. 这些新的TADF发射器增强了电荷传输,并实现了高外部量子效率,以提高OLED性能.
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 光物理学的光学物理学
背景情况:
- 有效的红/近红外 (NIR) 材料的有限可用性,具有热激活延迟光 (TADF).
- 控制单元电荷转移 (CT) 和三元局部激发 (LE) 状态之间的能量水平对齐的挑战,以提高排放效率.
- 需要扩大有机发光二极管 (OLED) 的高性能红色/深红色发射器池.
研究的目的:
- 设计和合成用于红色/深红色发射的新型捐赠-接受型TADF材料.
- 为了研究将4,4'-二甲三胺 (MeOTPA) 作为供体和硫 (S) 原子引入受体的效果.
- 为了增强电荷转移 (CT) 效应,并优化激发状态能量水平对齐以实现高效的TADF.
主要方法:
- 基于之前报告的绿色TADF材料 (67dTPA-FQ) 的分子设计.
- 合成了三种新的TADF材料:TQ-oMeOTPA,TsQ-oMeOTPA和SQ-oMeOTPA.
- 分析CT效应和能量水平对齐的理论计算.
- 使用合成材料制造和表征有机发光二极管 (OLED).
主要成果:
- 理论计算证实了由于MeOTPA和S原子的结合而增强的CT效应和调整的兴奋状态能量水平.
- 发光峰被成功转移到深红色区域.
- 基于SQ-oMeOTPA的OLED设备实现了高外部量子效率 (EQE) 19.1%,排放峰值在619nm.
结论:
- 这项研究成功地扩大了红色TADF材料的候选范围.
- 通过操纵兴奋状态能量水平来设计高效的发射器的可行性.
- 为快速选和开发各种TADF排放者提供了一个有价值的策略.
相关概念视频
Photoluminescence: Fluorescence and Phosphorescence
2.0K
Photoluminescence is a process where a molecule absorbs light energy and re-emits it in the form of light. This phenomenon occurs when a substance absorbs photons, promoting its electrons to higher energy level excited states, followed by a relaxation process in which the electrons return to their original ground state energy levels and emit light. Photoluminescence is widely observed in various materials, including semiconductors, and organic and inorganic compounds.
A pair of electrons in a...
A pair of electrons in a...
2.0K
Photoluminescence: Applications
393
Photoluminescence offers a wide range of applications due to its inherent sensitivity and selectivity. This technique allows for both direct and indirect analyses of the analyte. Direct quantitative analysis is possible when the analyte exhibits a favorable quantum yield for fluorescence or phosphorescence. However, an indirect analysis may be feasible if the analyte is not fluorescent or phosphorescent, or if the quantum yield is unfavorable. Indirect methods include reacting the analyte with...
393
Variables Affecting Phosphorescence and Fluorescence
498
Fluorescence and phosphorescence are essential phenomena in fields like analytical chemistry, biological imaging, and materials science, where they detect molecular properties and visualize cellular structures. Understanding the variables that influence these luminescent behaviors is crucial for maximizing accuracy and efficiency in their applications. These variables can broadly be grouped into chemical structure, solvent properties, and external conditions, each playing a distinct role in...
498
Deactivation Processes: Jablonski Diagram
645
Luminescence, the emission of light by a substance that has absorbed energy, is a process that involves the interaction of molecules with light. The energy-level diagram, or Jablonski diagram, is a graphical representation of these interactions, illustrating the various states and transitions a molecule can undergo. In a typical Jablonski diagram, the lowest horizontal line represents the ground-state energy of the molecule, which is usually a singlet state. This state represents the energies...
645
Protein Dynamics in Living Cells
2.1K
Different fluorescence-based techniques are used to study the protein dynamics in living cells. These techniques include FRAP, FRET, and PET.
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
2.1K
Super-resolution Fluorescence Microscopy
7.0K
Super-resolution fluorescence microscopy (SRFM) provides a better resolution than conventional fluorescence microscopy by reducing the point spread function (PSF). PSF is the light intensity distribution from a point that causes it to appear blurred. Due to PSF, each fluorescing point appears bigger than its actual size, and it is the PSF interference of nearby fluorophores that causes the blurred image. Various approaches to achieving higher resolution through SRFM have recently been...
7.0K


