# Energetics and Kinetics Requirements for Organic Solar Cells to 2 Break the 20% Power Conversion Efficiency Barrier Source: [Energetics and Kinetics Requirements for Organic Solar Cells to 2 Break the 20% Power Conversion Efficiency Barrier]() Collection index: [llms.txt]() Data updated: 2025-10-25T02:19:28.778Z Authors: Oskar J Sandberg, Ardalan Armin Published: 2021-04-23T00:30:10.000Z ## Abstract The thermodynamic limit for the efficiency of solar cells is predominantly defined by the energy bandgap of the used semiconductor. In case of organic solar cells both energetics and kinetics of three different species play role: excitons, charge transfer states and charge separated states. In this work, we clarify the effect of the relative energetics and kinetics of these species on the recombination and generation dynamics. Making use of detailed balance, we develop an analytical framework describing how the intricate interplay between the different species influence the photocurrent generation, the recombination, and the open-circuit voltage in organic solar cells. Furthermore, we clarify the essential requirements for equilibrium between excitons, CT states and charge carriers to occur. Finally, we find that the photovoltaic parameters are not only determined by the relative energy level between the different states but also by the kinetic rate constants. These findings provide vital insights into the operation of state-of-art non-fullerene organic solar cells with low offsets. ## Recorded benchmark results A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage. ## Original sources and implementation [Original paper]() [PDF]()