CdSe Quantum Dot-Fullerene Hybrid Nanocomposite for Solar Energy Conversion: Electron Transfer and Photoelectrochemistry
CdSe Quantum Dot-Fullerene Hybrid Nanocomposite for Solar Energy Conversion: Electron Transfer and Photoelectrochemistry
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DOI：
10.1021/nn204350w
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发表时间：
2011-12-01
期刊：
影响因子：
17.1
通讯作者：
Kamat, Prashant V.
中科院分区：
文献类型：
--
作者：
Bang, Jin Ho;Kamat, Prashant V.
有机/无机杂化纳米复合体系的发展对于太阳能电池研究的应用具有重要意义。纳米结构碳基系统，特别是C-60，提供了有吸引力的策略来收集和传输在光收集组件中产生的电子。我们通过将硫醇功能化的C-60与CdSe量子点(QD)进行化学连接，制备出了CdSe-C-60纳米复合材料。用暂态吸收光谱和光电化学方法研究了CdSe QD-C-60纳米复合材料中电子的光致电荷分离和收集。激发态CdSe量子点与C-60之间的电子转移速率常数随着量子点尺寸的减小而增大(7.9x10(9)S(-1)(4.5 nm)，1.7x10(10)S(-1)(3.2 nm)，9.0×10(10)S(-1)(2.6 nm))。在正向电子注入过程中，较慢的空穴转移和较快的电荷复合和传输事件被发现占主导地位，从而限制了CdSe QD-C-60太阳能电池中最大功率的传输。C60和CdSe量子点之间的光致电荷分离为发展光捕获组件开辟了新的设计策略。
The development of organic/inorganic hybrid nanocomposite systems that enable efficient solar energy conversion has been important for applications in solar cell research. Nanostructured carbon-based systems, in particular C-60, offer attractive strategies to collect and transport electrons generated in a light harvesting assembly. We have assembled CdSe-C-60 nanocomposites by chemically linking CdSe quantum dots (QDs) with thiol-functionalized C-60. The photoinduced charge separation and collection of electrons in CdSe QD-C-60 nanocomposites have been evaluated using transient absorption spectroscopy and photoelectrochemical measurements. The rate constant for electron transfer between excited CdSe QD and C-60 increased with the decreasing size of the CdSe QD (7.9 x 10(9) s(-1) (4.5 nm), 1.7 x 10(10) s(-1) (3.2 nm), and 9.0 x 10(10) s(-1) (2.6 nm)). Slower hole transfer and faster charge recombination and transport events were found to dominate over the forward electron injection process, thus limiting the deliverance of maximum power in CdSe QD-C-60-based solar cells. The photoinduced charge separation between CdSe QDs and C-60 opens up new design strategies for developing light harvesting assemblies.