Effect of the interface morphology on the fill factor of plastic solar cells

• Published in: Thin solid films Vol. 493; no. 1-2; pp. 273 - 277
• Main Authors: DJARA, V, BERNEDE, J. C
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier Science 22.12.2005
• Subjects: Applied sciences; Electrical, magnetic and optical properties; Energy; Exact sciences and technology; Natural energy; Organic polymers; Photoelectric conversion: solar cells and arrays; Photovoltaic conversion; Physicochemistry of polymers; Properties and characterization; Solar cells. Photoelectrochemical cells; Solar energy; Scanning electron microscopy; Voltage current curve; Diaminoanthraquinone; Fibrillar structure; Experimental study; Organic solar cells; Fill factor; Optical density; Solar cell; Conducting polymers; Thin films; Phthalocyanine; Acceptor donor pair; Anthraquinone; Morphology; Thiophene polymer; Interface; Organic compounds; Bilayers
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2005.06.098

Organic bilayer solar cells based on a donor/acceptor junction of zinc-phthalocyanine/1,4-diaminoanthraquinone (ZnPc/1,4-DAAQ) were studied. The transparent conductive oxide (TCO) electrode used was either the indium tin oxide (ITO) or the zinc oxide (ZnO), also the (poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid (PEDOT:PSS) was used as conductive polymer. Two different configurations were prepared: glass/ITO (or ZnO)/ZnPc/1,4-DAAQ/Al configuration and glass/Al/1,4-DAAQ/ZnPc/PEDOT:PSS/ ITO (or ZnO)/glass configuration. From the analysis of the current-voltage characteristics, the former presented a fill factor of 0DDT2, whereas the latter showed a fill factor of 0DDT5. Scanning electron microscopy images of the surface of the 1,4-DAAQ layer and the cross section of the overall structure were obtained. 1,4-DAAQ films revealed a highly fibrillar morphology. This special morphology is thought to have a preponderant effect on the fill factor, depending on the cell configuration.