Energy-level alignment at interfaces between manganese phthalocyanine and C60

We have used photoelectron spectroscopy to determine the energy-level alignment at organic heterojunctions made of manganese phthalocyanine (MnPc) and the fullerene C60. We show that this energy-level alignment depends upon the preparation sequence, which is explained by different molecular orientations. Moreover, our results demonstrate that MnPc/C60 interfaces are hardly suited for application in organic photovoltaic devices, since the energy difference of the two lowest unoccupied molecular orbitals (LUMOs) is rather small.

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Energy level alignment at interfaces in organic photovoltaic devices

Journal of Electron Spectroscopy and Related Phenomena ◽

10.1016/j.elspec.2012.11.008 ◽

2013 ◽

Vol 190 ◽

pp. 12-24 ◽

Cited By ~ 22

Author(s):

Andreas Opitz ◽

Johannes Frisch ◽

Raphael Schlesinger ◽

Andreas Wilke ◽

Norbert Koch

Keyword(s):

Energy Level ◽

Organic Photovoltaic ◽

Photovoltaic Devices ◽

Organic Photovoltaic Devices ◽

Energy Level Alignment

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Substrate dependence of energy level alignment at the donor–acceptor interface in organic photovoltaic devices

Journal of Electron Spectroscopy and Related Phenomena ◽

10.1016/j.elspec.2009.02.018 ◽

2009 ◽

Vol 174 (1-3) ◽

pp. 35-39 ◽

Cited By ~ 28

Author(s):

Y.C. Zhou ◽

Z.T. Liu ◽

J.X. Tang ◽

C.S. Lee ◽

S.T. Lee

Keyword(s):

Energy Level ◽

Organic Photovoltaic ◽

Photovoltaic Devices ◽

Organic Photovoltaic Devices ◽

Substrate Dependence ◽

Energy Level Alignment ◽

Donor Acceptor

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How to Control Component Ratio of Conducting Polymer Blend for Organic Photovoltaic Devices by Annealing

International Journal of Photoenergy ◽

10.1155/2015/532489 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Bobins Augustine ◽

Tapio Fabritius

Keyword(s):

Polymer Blends ◽

Conducting Polymer ◽

Polymer Blend ◽

Photoelectron Spectroscopy ◽

Conductivity Measurement ◽

Organic Photovoltaic ◽

Electrical Performance ◽

Component Ratio ◽

Photovoltaic Devices ◽

Organic Photovoltaic Devices

There are various conducting polymer blends which are used as hole transporting layers (HTL) in organic photovoltaic devices (OPV). The electrical performance of these conducting polymer blends depends crucially on its surface compositions and morphology. In this paper, we studied poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) or PEDOT:PSS as an example of the HTL conducting polymer blends used in OPV. We have investigated the effect of annealing PEDOT:PSS in different atmospheres such as vacuum, N2, and air at different temperatures. It was found that the component ratio of the polymer blend is changing with annealing temperature and atmosphere. PSS/PEDOT ratio was found to have clear influence on the electrical performance of the material. In practice, we found that annealing can be used as a method to control component ratio of the HTL conducting polymer blend to achieve better electrical performance in OPV devices. The component ratio changes of the polymer with annealing were understood by X-ray photoelectron spectroscopy (XPS). Annealing in N2atmosphere at 220°C for 1 hour gave best electrical performance for the polymer and the PSS/PEDOT ratio at that condition was close to 1.1, while the initial ratio was 2.5. Optimizing HTL layer by simple conductivity measurement does not guarantee best performance in OPV since surface property changes during annealing might affect the deposition of successive active layers on top and thus final device. Thus we have optimized annealing condition of the HTL layer according to the OPV performance itself.

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