Dresden 2017 – wissenschaftliches Programm
CPP 70.3: Vortrag
Freitag, 24. März 2017, 10:45–11:00, ZEU 255
Energy losses in organic small molecule photovoltaics — •Theresa Linderl, Alexander Hofmann, Thomas Zechel, and Wolfgang Brütting — Universität Augsburg, 86135 Augsburg, Germany
One of the most important factors that limits the efficiency of organic photovoltaics is the relatively large energy loss between the optical gaps of the neat materials and the open-circuit voltage VOC.
Partly, this can be explained by the energetic offset between the energy levels of the donor and acceptor material, which is often called the driving force to form the charge transfer complex. The energy of this charge transfer complex is regarded as the upper limit for VOC at 0 K. In contrast, at room temperature VOC is further reduced by radiative and non-radiative recombination losses.
By combining different donors with fullerene and non-fullerene acceptor materials, we have investigated the influence of interface energetics, molecular orientation and morphology on the total energy loss in organic small molecule solar cells. We find, that for proper non-fullerene acceptor materials the overall loss can be significantly reduced to about 0.6 eV, which is comparable to the best polymer solar cells.