| Abstract [eng] |
In the search for alternative power generation sources, organic photovoltaics seem to be one of the most attractive options for certain niche applications. Recently, their power conversion efficiency has skyrocketed thanks to the introduction of a new generation of acceptor molecules. Nevertheless, the physical understanding of the underlying mechanisms remains poorly understood. This dissertation is devoted to the study of all important dynamic processes, such as the generation and extraction of free charge carriers in non-fullerene organic solar cells. Various transient measurement techniques and their improvements have been employed to study each step in the operation of organic solar cells over an exceptionally wide temporal range, from femto- to microseconds. In this work, the effects of spatial trapping of charge carriers in bulk heterojunction organic solar cells, as well as the dynamics of charge carrier extraction dynamics at close to real working conditions in organic solar cells, and the specifics of charge carrier generation in novel organic solar cells based on non-fullerene acceptors have been investigated. This has led to a better understanding of the physical processes in organic photovoltaic devices and contributed to their further improvement. |
