Controlling Polarization-Induced Polaron Accumulation in OLEDs via Device Design
E. Pakhomenko, S. Martin, S. He, A. Kapur, R. J. Holmes, Adv. Funct. Mater. 2025, 35, 2412329. https://doi.org/10.1002/adfm.202412329
The goal of this study was to control polarization-induced polaron accumulation in organic light-emitting devices (OLEDs) through strategic device design, aiming to enhance efficiency and reduce exciton-polaron quenching (EPQ).
Key findings showed that by either using a polar emissive host material or inserting a spacer layer at the hole transport/emissive layer interface, it is possible to shift and control the location and dynamics of polaron accumulation. OLEDs with polar hosts showed improved internal quantum efficiency (IQE) by ~10%, attributed to reduced EPQ. Spacer layers further modulated charge accumulation dynamics post-turn-on, leading to significant efficiency improvements without compromising charge balance.
Fluxim’s Setfos software was used to simulate optical outcoupling efficiencies, ensuring that measured improvements in device performance were linked to electronic and excitonic behaviors rather than optical artifacts. Setfos provided precise modeling of optical constants and emission characteristics, supporting quantitative analysis of IQE enhancements.
These findings are important because they offer a practical, architecture-driven pathway to mitigate polarization effects in OLEDs without requiring complex material redesign, thus helping to improve the stability and efficiency of future display and lighting technologies.