Dresden 2014 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 21: Organic Semiconductors: Photovoltaics (original: HL, joined by CPP, DS)

CPP 21.5: Vortrag

Dienstag, 1. April 2014, 11:00–11:15, POT 081

Imaging the origin of S-shaped current-voltage characteristics of organic solar cells by scanning Kelvin probe microscopy — •Christian Müller^1,2,3, Rebecca Saive^1,2,3, Janusz Schinke^1,3, Robert Lovrincic^1,3, and Wolfgang Kowalsky^1,2,3 — ¹InnovationLab GmbH, Heidelberg, Germany — ²Kirchhoff-Institut für Physik, University Heidelberg, Germany — ³Institut für Hochfrequenztechnik, Technische Universität Braunschweig, Germany

We investigated organic bilayer solar cells consisting of poly(3-hexylthiophene)/1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C61 (P3HT/PCBM). Scanning Kelvin probe microscopy (SKPM) was performed on the solar cell cross sections which were exposed with a focused ion beam. We prepared the P3HT/PCBM bilayer solar cells by solution processing. These bilayer solar cells showed normal and anomalous, S-shaped current-voltage characteristics. Using SKPM on the device cross sections, we found that in normal bilayer solar cells the potential dropped at the ITO/PEDOT:PSS contact and over the active area, whereas in S-shaped bilayer solar cells the potential dropped exclusively at the aluminium contact. This behavior confirms the assumption that S-shaped curves are caused by hindered charge transport at electrode interfaces.