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arXiv · 1401.1967

Electronic properties and morphology of Cu-Phthalocyanine - C$_{60}$ composite mixtures

Friedrich Roth·Cosmin Lupulescu·Tiberiu Arion·Erik Darlatt·Alexander Gottwald·Wolfgang Eberhardt
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Abstract

Phthalocyanines in combination with C$_{60}$ are benchmark materials for organic solar cells. Here we have studied the morphology and electronic properties of co-deposited mixtures (blends) of these materials forming a bulk heterojunction as a function of the concentration of the two constituents. For a concentration of 1:1 of CuPc:C$_{60}$ a phase separation into about 100 nm size domains is observed, which results in electronic properties similar to layered systems. For low C$_{60}$ concentrations (10:1 CuPc:C$_{60}$) the morphology, as indicated by Low-Energy Electron Microscopy (LEEM) images, suggests a growth mode characterized by (amorphous) domains of CuPC, whereby the domain boundaries are decorated with C$_{60}$. Despite of these markedly different growth modes, the electronic properties of the heterojunction films are essentially unchanged.

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Friedrich Roth, Cosmin Lupulescu, Tiberiu Arion, Erik Darlatt, Alexander Gottwald, Wolfgang Eberhardt. 2014-01-09. Electronic properties and morphology of Cu-Phthalocyanine - C$_{60}$ composite mixtures. https://doi.org/10.1063/1.4861886

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