| 초록 |
The rapid development of organic solar cells (OSCs) based on non-fullerene acceptors (NFAs) has attracted increasing attention during the past few years, with a record power conversion efficiencies (PCEs) of over 15% in the bulk-heterojunction single cells. This NFAs mostly synthesized between aldehyde and active hydrogen compounds via the Knoevenagel condensation. A Knoevenagel condensation is a nucleophilic addition of an active hydrogen compound to a carbonyl group followed by a dehydration reaction in which a molecule of water is eliminated. Sometimes, it would cause the isomerization of NFAs, this is hard to separate the isomers for purification, and burden to the mass production with high purity. In this study, we demonstrate the relationship between (Z) and (E) stereoisomers through the synthesizing 3,4-ethylenedioxythiophene (EDOT)-based NFAs. Moreover, we succeeded to get dominant (Z) isomer among the EDOT-based NFAs by controlling steric hindrance and synthetic process. |
