期刊
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
卷 139, 期 21, 页码 7287-7293出版社
AMER CHEMICAL SOC
DOI: 10.1021/jacs.7b01550
关键词
-
资金
- U.S. National Science Foundation [NSF-CHE-1555005]
Long-range exciton transport is a key challenge in achieving efficient solar energy harvesting in both organic solar cells and photosynthetic systems. Self-assembled molecular aggregates provide the potential for attaining long-range exciton transport through strong intermolecular coupling. However, there currently lacks an experimental tool to directly characterize exciton transport in space and in time to elucidate mechanisms. Here we report a direct visualization of exciton diffusion in tubular molecular aggregates by transient absorption microscopy with similar to 200 fs time resolution and similar to 50 nm spatial precision. These direct measurements provide exciton diffusion constants of 3-6 cm(2) s(-1) for the tubular molecular aggregates, which are 3-5 times higher than a theoretical lower bound obtained by assuming incoherent hopping. These results suggest that coherent effects play a role, despite the fact that exciton states near the band bottom crucial for transport are only weakly delocalized (over <10 molecules). The methods presented here establish a direct approach for unraveling the mechanisms and main parameters underlying exciton transport in large molecular assemblies.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据