缺失的刺激:能量转移如何与稀释-捐赠者/接受器系统中的免费充电产生竞争
Joshua M Carr1, Melissa K Gish2, Obadiah G Reid2,3
1Materials Science and Engineering Program, University of Colorado Boulder, Boulder, Colorado 80303, United States.
概括
在有机光伏中,超快的能量传输可以通过抑制电荷生成来阻碍性能. 这项研究揭示了一种最佳的能量转移驱动力,以最大限度地提高捐赠者-接受者系统中的自由电荷产量.
科学领域:
- 有机光伏是有机的光伏.
- 摄影化学的使用.
- 能源转移动态的动态.
背景情况:
- 在有机光伏中,能量转移对于电荷产生至关重要.
- 通常情况下,捐赠者-接受器能量传输可以提高设备的性能.
- 然而,特定的分子安排可能会导致有害的能量传输途径.
研究的目的:
- 在有机光伏中研究一个场景,在这种场景中,激发能量转移 (EET) 抑制了免费的发电.
- 阐明在稀释的捐赠-接受系统中电荷生成和ETE之间的竞争.
- 确定光化学驱动力在优化充电产量的作用.
主要方法:
- 时间解析微波导电率 (TRMC) 检测免费电荷的产生.
- 暂时吸收光谱学用于研究刺激子动态.
- 分析能量转移路径和电荷转移状态的形成.
主要成果:
- 在接受宿主中的稀释供体分子表现出超快激发能量转移 (EET).
- 这种EET抑制了免费运营商的收益率.
- 观察到一个最佳的光化学驱动力,用于免费充电生成,但产量低.
- 转移的激子有效地形成电荷转移状态,与自由电荷生成竞争.
结论:
- 激发能量转移到宿主矩阵可能会对有机光伏的性能产生不利影响.
- 长距离电子转移 (产生自由电荷) 和EET (产生局部电荷转移状态) 之间存在竞争.
- 这些发现挑战了局部电荷转移状态仅仅是刺激子和自由电荷之间的中间体的模型.
相关概念视频
Carrier Generation and Recombination
572
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...
572
Ion Exchange
591
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or...
591
Oxidation and Reduction of Organic Molecules
6.5K
Energy production within a cell involves many coordinated chemical pathways. Most of these pathways are combinations of oxidation and reduction reactions, which occur at the same time. An oxidation reaction strips an electron from an atom in a compound, and the addition of this electron to another compound is a reduction reaction. Because oxidation and reduction usually occur together, these pairs of reactions are called redox reactions.
The removal of an electron from a molecule, results in a...
The removal of an electron from a molecule, results in a...
6.5K
Electrolysis
26.3K
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...
26.3K
Electron Carriers
84.5K
Electron carriers can be thought of as electron shuttles. These compounds can easily accept electrons (i.e., be reduced) or lose them (i.e., be oxidized). They play an essential role in energy production because cellular respiration is contingent on the flow of electrons.
Over the many stages of cellular respiration, glucose breaks down into carbon dioxide and water. Electron carriers pick up electrons lost by glucose in these reactions, temporarily storing and releasing them into the electron...
Over the many stages of cellular respiration, glucose breaks down into carbon dioxide and water. Electron carriers pick up electrons lost by glucose in these reactions, temporarily storing and releasing them into the electron...
84.5K
Aqueous Solutions and Heats of Hydration
14.7K
Water and other polar molecules are attracted to ions. The electrostatic attraction between an ion and a molecule with a dipole is called an ion-dipole attraction. These attractions play an important role in the dissolution of ionic compounds in water.
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
14.7K


