Fullerene-free bulk heterojunction blends for organic electronics (R-8151)

Over the past decades, organic semiconductors have become increasingly popular because of their ability to combine the electronic properties of semiconducting materials with the mechanical and chemical versatility of organic compounds. As such, they have been applied in multiple electronic devices. In the field of organic photovoltaics (OPVs), the bulk heterojunction (BHJ) photoactive layer concept has surely demonstrated its value, as power conversion efficiencies over 11% have recently been reported. State of the art organic photodetectors (OPDs) consist of the same donor:acceptor BHJ architecture. For a long time, fullerenes have been the dominating class of electron acceptor molecules in both types of devices, but recent noteworthy results have caused a paradigm shift to alternative non-fullerene systems, with considerable advantages in terms of cost, tunability, absorptivity and stability. Despite the impressive progress in solar cell efficiency, a detailed understanding of structure - BHJ morphology - device property relations for novel fullerene-free blends remains noticeably absent. Therefore, this project envisages a detailed fundamental understanding of how molecular engineering of alternative acceptor molecules influences the BHJ blend morphology and thereby the performance of OPVs and OPDs. To this extent, a set of very complementary blend analysis techniques will be employed. The (thermal) stability of the novel blends will be investigated as well.

Keywords:POLYMER NETWORKS, SOLAR CELLS

Disciplines:Macromolecular and materials chemistry, Organic chemistry, Process engineering, Polymeric materials