The Origin of Charge Localization Observed in Organic Photovoltaic Materials

被引：38

作者：

Johns, James E. ^{[1
]}

Muller, Eric A. ^{[1
]}

Frechet, Jean M. J. ^{[1
]}

Harris, Charles B. ^{[1
]}

机构：

[1] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2010年 / 132卷 / 44期

关键词：

FEMTOSECOND DYNAMICS; SOLAR-CELLS; ELECTRON; MORPHOLOGY; MOBILITY; POLYMER; PHOTOEMISSION; TRANSPORT;

D O I：

10.1021/ja1066866

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Two of the primary hurdles facing organic electronics and photovoltaics are their low charge mobility and the inability to disentangle morphological and molecular effects on charge transport. Specific chemical groups such as alkyl side chains are often added to enable spin-casting and to improve overall power efficiency and morphologies, but their exact influence on mobility is poorly understood. Here, we use two-photon photoemission spectroscopy to study the charge transport properties of two organic semiconductors, one with and one without alkyl substituents (sexithiophene and dihexyl-sexithiophene). We show that the hydrocarbon side chains are responsible for charge localization within 230 fs. This implies that other chemical groups should be used instead of alkyl ligands to achieve the highest performance in organic photovoltaics and electronics.

引用

页码：15720 / 15725

页数：6

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