Competition between singlet exciton fission, radiation, and dissociation measured in rubrene-doped amorphous films

In singlet fission sensitized photovoltaic devices, the photoexcited singlet excitons might undergo three different decay pathways including fission, radiation, and dissociation. For rubrene-doped amorphous films, we analyzed the competition between these three decay channels by using transient and steady-state measurements of photoluminescence and photocurrent, as well as their magnetic field effects. The experimental results and theoretical calculations show that the internal quantum efficiency of our device can reach about 124%. More importantly, the method developed in this work can also be applied to other fission materials for optimizing the design of fission sensitized photovoltaic devices. (C) 2015 Elsevier B.V. All rights reserved.