Regensburg 2019 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 31: Organic Electronics and Photovoltaics II - Non-Fullerene Organic Solar Cells

CPP 31.5: Talk

Wednesday, April 3, 2019, 10:30–10:45, H18

Long term UV stable organic solar cells by utilizing a stable donor-acceptor-additive combination — •Thomas Heumüller, Andrej Classen, Yakun He, Lukas Einsiedler, Johannes Gerner, Ning Li, and Christoph Brabec — Friedrich-Alexander-Universität Erlangen-Nürnberg

With the advent of non-fullerene acceptors (NFA), current state of the art organic solar cells (OSC) reach efficiencies around 14 % and an efficiency of 10 % is surpassed for plenty of systems. However, little is known about the stability and lifetime of current NFA based OSCs. Here we present a detailed degradation analysis of OSCs based on a polymer (PBQ-QF) which exhibits a good performance when blended with two different NFAs (ITIC and o-IDTBR) as well as PC70BM. In order to separate effects from several different degradation mechanisms that usually occur at the same time, we perform tests under controlled environmental conditions to avoid photo-oxidation and we focus on the degradation in dependence of UV light. Under full AM 1.5G light spectrum (1000 h continuous illumination) we observe an intense degradation of PBQ-QF:PC70BM while PBQ-QF:ITIC exhibits a moderate stability and PBQ-QF:o-IDTBR is highly stable. Interestingly we find, that the strong degradation of PBQ-QF:PC70BM can be lifted when UV cut-off filters are applied. The in-depth analysis reveals that the UV instability originates from a UV instability of PC70BM towards the processing additive 1,8 diiodooctane.