The Effect of Energy Levels of the Electron Acceptor Materials on Organic Photovoltaic Cells

Hassen Derouiche, Sami Saidi, Abdelatif Belhadj Mohamed

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Laboratoire de Photovolta?ques, Centre de Recherches et des Technologies de l’Energie, BP 95, 2050 Hammam-Lif, Tunisia.

DOI: 10.4236/sgre.2011.23031                

Abstract

Organic photovoltaic cells have been fabricated using copper phthalocyanine CuPc as electron donor and C60 or PCBM as electron acceptor. We have investigated the I-V measurements of two different structures: ITO/PEDOT: PSS/(CuPc:C60 or CuPc:PCBM)/BCP/Al. We have observed that the substitution of PCBM by C60 scales up the photocurrent and the efficiency of the devices. As for the open-circuit voltage and the fill factor, we have seen that Voc and FF depend on the energy difference between the highest occupied molecular orbital (HOMO) of CuPc and the lowest unoccupied molecular orbital (LUMO)of C60 or PCBM.

Keywords

CuPc, C60, PCBM, Energy Levels, Organic Photovoltaic Cells

Conflicts of Interest

The authors declare no conflicts of interest.

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