The Influence of Conjugated Polymer Side Chain Manipulation on the Efficiency and Stability of Polymer Solar Cells

Materials

Morten V. Madsen¹  Ilona M. Heckler¹  Eva Bundgaard¹  Jan D’Haen²  Wouter Maes²  Huguette Penxten²  Jurgen Kesters²  Bruno Van Mele³  Maxime Defour³ 

[1] Department of Energy Conversion and Storage, Technical University of Denmark (DTU), Frederiksborgvej 399, Roskilde 4000, Denmark;Institute for Materials Research (IMO-IMOMEC), Hasselt University, Agoralaan 1-Building D, Diepenbeek 3590, Belgium;Physical Chemistry and Polymer Science (FYSC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, Brussels 1050, Belgium;

关键词: conjugated polymers;    side chain variation;    organic photovoltaics;    roll-coating;    photochemical and thermal stability;   

DOI  :  10.3390/ma9030181

来源: DOAJ

【 摘 要 】

The stability of polymer solar cells (PSCs) can be influenced by the introduction of particular moieties on the conjugated polymer side chains. In this study, two series of donor-acceptor copolymers, based on bis(thienyl)dialkoxybenzene donor and benzo[c][1,2,5]thiadiazole (BT) or thiazolo[5,4-d]thiazole (TzTz) acceptor units, were selected toward effective device scalability by roll-coating. The influence of the partial exchange (5% or 10%) of the solubilizing 2-hexyldecyloxy by alternative 2-phenylethoxy groups on efficiency and stability was investigated. With an increasing 2-phenylethoxy ratio, a decrease in solar cell efficiency was observed for the BT-based series, whereas the efficiencies for the devices based on the TzTz polymers remained approximately the same. The photochemical degradation rate for PSCs based on the TzTz polymers decreased with an increasing 2-phenylethoxy ratio. Lifetime studies under constant sun irradiance showed a diminishing initial degradation rate for the BT-based devices upon including the alternative side chains, whereas the (more stable) TzTz-based devices degraded at a faster rate from the start of the experiment upon partly exchanging the side chains. No clear trends in the degradation behavior, linked to the copolymer structural changes, could be established at this point, evidencing the complex interplay of events determining PSCs’ lifetime.

【 授权许可】

Unknown