在自我组装的氨酸衍生物层中有效的激子传输
Annemarie Huijser1, Bart M J M Suijkerbuijk, Robertus J M Klein Gebbink
1Opto-Electronic Materials Section, DelftChemTech, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands.
Journal of the American Chemical Society
|February 6, 2008
概括
研究人员模仿了自然光采集系统,创造了自组装的氨酸分子. 这种人工系统实现了长激子扩散长度,与自然色素相比,显示了光电子学的前景.
科学领域:
- 材料科学 材料科学 材料科学
- 摄影化学的使用.
- 生物物理学的生物物理.
背景情况:
- 绿硫细菌的基因组是非常高效的自然光采集系统,这是由于细菌菌的自我组装.
- 高效的刺激子传输对于光采集系统至关重要,这些系统起源于分子自我组装.
- 人工系统可以从模仿自然的自我组装原理中受益,以改善激子传输.
研究的目的:
- 为了创建一个具有长激子扩散长度的人工光收获系统.
- 为了利用自组装的自然染色体染色体的概念.
- 为了研究自我组装的氨酸衍生物中的激子运输.
主要方法:
- 氨酸衍生物的合成和表征,具有不同的自我组装倾向 (ZnOP和ZnBuP).
- 制造由氨酸衍生物和TiO2组成的双层系统.
- 时间解析微波导电性 (TRMC) 测量以研究激子传输和解离.
主要成果:
- ZnOP形成了自我组装的堆,表现出15 ± 1纳米的激子扩散长度,与自然色素相比.
- ZnBuP显示了显著更短的3 ± 1纳米的激子扩散长度.
- 由于用于堆间能量传输的强烈刺激合,ZnOP表现出更高的激子扩散系数 (1.4 x 10^-6 m2/s).
结论:
- 分子组织强烈影响人工光采集系统中的能量传输效率.
- 自组装的氨酸衍生物,如ZnOP,可以实现长的刺激子扩散长度.
- 这些发现表明,自我组装的氨酸在光电子产品中具有有前途的应用.
相关概念视频
01:26Photochemical Electrocyclic Reactions: Stereochemistry
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
01:27Photosystem I
Although structurally similar to photosystem II (PSII), photosystem I (PSI) is has a different electron supplier and electron acceptor.
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
01:15The Antenna Complex
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01:34The Z-Scheme of Electron Transport in Photosynthesis
The light reactions of photosynthesis assume a linear flow of electrons from water to NADP+. During this process, light energy drives the splitting of water molecules to produce oxygen. However, oxidation of water molecules is a thermodynamically unfavorable reaction and requires a strong oxidizing agent. This is accomplished by the first product of light reactions: oxidized P680 (or P680+), the most powerful oxidizing agent known in biology. The oxidized P680 that acquires an electron from the...
01:26Thermal and Photochemical Electrocyclic Reactions: Overview
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.
01:22Photosystem II
The multi-protein complex photosystem II (PS II) harvests photons and transfers their energy through its bound pigments to its reaction center, and ultimately to photosystem I (PSI) through the electron transport chain. The pigments responsible for caputirng the light energy in photosystems include chlorophyll a, chlorophyll b, and carotenoids.
The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment molecules...
The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment molecules...