Regensburg 2019 – wissenschaftliches Programm
HL 45.23: Poster
Donnerstag, 4. April 2019, 18:30–21:00, Poster E
Investigating Oxygen Degradation in PCE-11 Solar Cells — •Andreas Weu and Joshua Kress — Centre for Advanced Materials, Heidelberg
Recently, the efficiency of organic solar cells was improved to over 13%, bringing organic photovoltaics one step closer to serious commercialisation. However, the environmental stability of such devices, which is an essential step towards further development, remains rather insufficiently understood. Here, we address the effect of oxygen on the operation of the high-efficiency material system PCE-11:PC71BM. By using ultra-fast transient absorption (TA) and ultra-sensitive photo-thermal deflection (PDS) techniques in combination with field-effect transistors, we show that oxygen-induced doping of the active layer is mainly responsible for the observed device degradation. We find that exposure to light is accelerating this effect without causing photo-oxidation of the materials.