Start of funding 01.07.2017

Origin of the Open Circuit Voltage in Organic Ternary Solar Cells

Dr. Tayebeth Ameri
Friedrich-Alexander-University of Erlangen-Nuremberg
Department of Materials Science and Engeneering

Prof. Barry C. Thompson
University of Southern California, Los Angeles
Loker Hydrocarbon Research Institute



The open circuit voltage (Voc) in organic ternary solar cells has been a hot research topic for a few years. Apparently, in many ternary blend solar cells the Voc is not limited to the minimum Voc of the binary references. The dependence of Voc on the sensitizer concentration has been reported by several groups. Although different hypotheses are reported in literature to explain the origin of Voc increase, no clear proof and distinguishable approach has been presented so far. In this work, we will investigate the influence of the sensitizer content on the Voc for different ternary blend systems. To illuminate on the origin of the Voc and to find the share of suppressed energetic losses involved in the Voc enhancement, we will employ different optoelectronic spectroscopy techniques. Furthermore, we will perform Monte Carlo simulation to correlate the experimental results to the literature proposed morphological models. This unprecedented work allows us to correlate nano-morphological features with measured optical properties and obtained Voc, a crucial capability for the design of optimized, high performance ternary solar cells.