Tuning the driving force for exciton dissociation in single-walled carbon nanotube heterojunctions
Tuning the driving force for exciton dissociation in single-walled carbon nanotube heterojunctions
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DOI：
10.1038/nchem.2496
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发表时间：
2016-06-01
期刊：
影响因子：
21.8
通讯作者：
Blackburn, Jeffrey L.
中科院分区：
文献类型：
--
作者：
Ihly, Rachelle;Mistry, Kevin S.;Blackburn, Jeffrey L.
了解分子体系中界面电子转移的动力学和能量学对于发展包括光伏、太阳能燃料系统和储能在内的一系列广泛的技术至关重要。电子转移的马库斯公式将给定的给体/受体对之间电荷转移的热力学推动力和重组能与电子转移的动力学和产额联系起来。本文采用时间分辨微波电导作为界面激子解离的灵敏探针，研究了单壁碳纳米管(SWCNTs)与富勒烯衍生物之间光诱导电子转移(PET)的热力学驱动力的影响。我们首次观察到了马库斯反转区(驱动力超过重组能)，并对模型SWCNT/受体体系的PET重组能进行了量化。较小的重组能(约130 meV，其中大部分可能来自富勒烯受体)有利于最小化光转化方案中的能量损失。
Understanding the kinetics and energetics of interfacial electron transfer in molecular systems is crucial for the development of a broad array of technologies, including photovoltaics, solar fuel systems and energy storage. The Marcus formulation for electron transfer relates the thermodynamic driving force and reorganization energy for charge transfer between a given donor/acceptor pair to the kinetics and yield of electron transfer. Here we investigated the influence of the thermodynamic driving force for photoinduced electron transfer (PET) between single-walled carbon nanotubes (SWCNTs) and fullerene derivatives by employing time-resolved microwave conductivity as a sensitive probe of interfacial exciton dissociation. For the first time, we observed the Marcus inverted region (in which driving force exceeds reorganization energy) and quantified the reorganization energy for PET for a model SWCNT/acceptor system. The small reorganization energies (about 130 meV, most of which probably arises from the fullerene acceptors) are beneficial in minimizing energy loss in photoconversion schemes.