在推拉半导体聚合物中激发双分子消灭动力学
Yulong Zheng1, Rahul Venkatesh2, Esteban Rojas-Gatjens1
1School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332, United States.
The journal of physical chemistry letters
|January 2, 2024
概括
结合聚合物的兴奋子-兴奋子灭绝是使用光谱学研究的. 一维扩散控制了毁灭速率,揭示了对非线性激子动态的洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 有机电子 有机电子
背景情况:
- 兴奋子-兴奋子消灭是Frenkel兴奋子系统中的一个关键的非线性过程.
- 了解这些动态对于光电子设备的效率至关重要.
研究的目的:
- 研究电子推拉合聚合物的非线性激子动力学.
- 确定激发流动对激发灭的影响.
- 确定刺激子扩散和重组的潜在机制.
主要方法:
- 流动依赖的短暂吸收光谱学.
- 激发相关光光谱学.激发相关光光谱学.
- 时间独立的激发物灭绝模型.
主要成果:
- 激发相关光发光是一种对非线性动态的选择性探测器.
- 随着激发流动度的增加,消灭率会降低.
- 兴奋剂-兴奋剂消灭率表现出t-1/2时间依赖,表明1D扩散.
- 估计刺激子扩散长度为9 ± 2nm.
- 刺激的消灭产生了一种长寿的物种,具有纳米秒的重组.
结论:
- 一维激子扩散显著影响推拉合聚合物的灭绝率.
- 观察到的时间依赖提供了对非线性刺激子行为的新理解.
- 这些发现对设计高效的有机电子材料具有广泛的影响.
相关概念视频
Carrier Generation and Recombination
577
Carrier generation is the process by which electron-hole pairs (EHPs) are created within the semiconductor. In direct-bandgap semiconductors, such as gallium arsenide (GaAs), this occurs efficiently when energy absorption prompts valence electrons to leap into the conduction band, leaving behind holes.
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
577
Deactivation Processes: Jablonski Diagram
667
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...
667
Cationic Chain-Growth Polymerization: Mechanism
2.3K
The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the...
2.3K
Thermal and Photochemical Electrocyclic Reactions: Overview
2.3K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.3K
Fermi Level Dynamics
252
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
252
Anionic Chain-Growth Polymerization: Mechanism
2.0K
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael...
2.0K


