高效的电子传输和敏感剂再生在稳定的pi-扩展四亚富烯敏感的太阳能电池中
Sophie Wenger1, Pierre-Antoine Bouit, Qianli Chen
1Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Federale de Lausanne (EPFL), Station 6, CH-1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|March 24, 2010
概括
无金属有机敏化剂对于染料敏化太阳能电池至关重要. 新的四甲衍生物证明了高效的再生,使光伏设备即使具有很小的再生驱动力也能够发挥功能.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 太阳能光伏发电是如何实现的
背景情况:
- 无金属有机敏化剂对于推进染料敏化太阳能电池 (DSSC) 技术至关重要.
- 实现高效的光伏转换需要仔细考虑传感器特性及其与氧化还原介质的相互作用.
研究的目的:
- 开发和表征新型,稳定的四甲 (TTF) 衍生物作为DSSCs的无金属有机敏感剂.
- 调查这些TTF敏化器的电化学和运动性质及其再生效率.
主要方法:
- 合成和描述新的四甲衍生物.
- 使用半孔TiO(2) 薄膜和TFT传感器制造光伏设备.
- 时间分辨率光谱学研究光氧化感应剂的再生动力学通过化/三化氧化还原介质.
主要成果:
- 通过新的基于TFT的有机敏感剂,成功实现了光伏转换.
- 观察到光氧化TFT感应器的高效再生,即使再生的驱动力低至大约150mV.
- 该研究表明,具有较小驱动力的敏感剂可以在DSSC中有效运行.
结论:
- 新型四甲衍生物代表着对染料敏感化太阳能电池的一类有希望的无金属有机敏化剂.
- 使用最小的驱动力可以实现敏感器的高效再生,提供减少光伏损失的策略.
- 这项工作为开发具有更好的能量对齐的高性能DSSC提供了关键的概念验证.
相关概念视频
Photochemical 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
Photosystem 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...
The 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...
Photosystem 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...
Thermal 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.
The Antenna Complex
Plants and other photosynthetic organisms comprise pigments capable of absorption of direct sunlight. These pigments are present in the reaction center - the main site of photochemical reactions as well as in the antenna complex. Under average light conditions, the rate at which reaction center pigments absorb light is far below the electron transport chain's capacity. As a result, the reaction center alone cannot provide enough energy to drive photosynthesis. The photosynthetic efficiency can...


