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arXiv · 1511.00809

Electronic properties of Mn-Phthalocyanine - C$_{60}$ bulk heterojunctions: combining photoemission and electron energy-loss spectroscopy

Friedrich Roth·Melanie Herzig·Cosmin Lupulescu·Erik Darlatt·Alexander Gottwald·Martin Knupfer·Wolfgang Eberhardt
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Abstract

The electronic properties of co-evaporated mixtures (blends) of manganese phthalocyanine and the fullerene C$_{60}$ (MnPc:C$_{60}$) have been studied as a function of the concentration of the two constituents using two supplementary electron spectroscopic methods, photoemission spectroscopy (PES) as well as electron energy-loss spectroscopy (EELS) in transmission. Our PES measurements provide a detailed picture of the electronic structure measured with different excitation energies as well as different mixing ratios between MnPc and C$_{60}$. Besides a relative energy shift, the occupied electronic states of the two materials remain essentially unchanged. The observed energy level alignment is different compared to that of the related CuPc:C$_{60}$ bulk heterojunction. Moreover, the results from our EELS investigations show that despite of the rather small interface interaction the MnPc related electronic excitation spectrum changes significantly by admixing C$_{60}$ to MnPc thin films.

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Friedrich Roth, Melanie Herzig, Cosmin Lupulescu, Erik Darlatt, Alexander Gottwald, Martin Knupfer, Wolfgang Eberhardt. 2015-11-03. Electronic properties of Mn-Phthalocyanine - C$_{60}$ bulk heterojunctions: combining photoemission and electron energy-loss spectroscopy. https://doi.org/10.1063/1.4935623

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