Researchers from the FAU Erlangen-Nürnberg, including Marc Steinberger, Maxime Siber, and Christoph J. Brabec, along with collaborators from other institutions, have published a study in the journal Nature Communications that sheds light on the impact of drying time on the performance of organic solar cells. The team’s findings could have significant implications for the industrial-scale production of these promising photovoltaic devices.
Organic solar cells, which use organic materials to convert sunlight into electricity, have gained attention due to their potential for low-cost, large-area, and flexible applications. However, scaling up their production from laboratory settings to industrial processes often leads to performance losses. One key factor that can influence the efficiency of these devices is the rate at which the solvent used in their production evaporates.
The researchers set out to isolate and understand the influence of solvent drying rate on the nanomorphology and performance of PM6:Y6 organic solar cells. They employed a specially designed gas quenching technique to fabricate films under controlled evaporation conditions. By combining numerical simulations and experimental measurements, they were able to unravel the process-structure-performance relationships in these solar cells.
The study found that higher drying rates result in finer and more dispersed nanomorphologies, with increased fractions of amorphous material. This enhancement in the material’s structure leads to improved electric charge generation, boosting the short-circuit current density and overall cell performance. Additionally, the open-circuit voltage was found to increase under accelerated evaporation due to changes in the aggregation mode of the Y6 small molecule, which induces higher effective bandgaps.
The developed gas-quenching technique is notable for its compatibility with high-throughput equipment, such as roll-to-roll coating machines, making it a valuable tool for optimizing the performance of upscaled organic photovoltaics. This research provides practical insights for the energy sector, particularly in the manufacturing of organic solar cells, by demonstrating how controlling the drying process can enhance device efficiency and facilitate industrial-scale production.
Source: Steinberger, M., Siber, M., Egelhaaf, H.J. et al. Understanding the effect of drying time in process-structure-performance relationships for PM6-Y6 organic solar cells. Nat Commun 15, 1124 (2024).
This article is based on research available at arXiv.