Project R-16257

Polymeric semiconductors for amplified circularly polarized electroluminescence (Research)

Organic light-emitting diodes (OLEDs) that afford high levels of circularly polarized (CP) light hold significant promise for numerous future technologies (e.g. power-efficient displays, optical spintronics, quantum information). Such devices require chiral emitters to enable CP-electroluminescence. However, developing CP-OLEDs that achieve strong chiroptical activity, high efficiency, and narrow-spectrum emission remains very challenging. The majority of current chiral emitters, including the state-of-the-art triplet-harvesting thermally activated delayed fluorescence (TADF) materials, produce very low levels of CP-(electro)luminescence, below the application threshold. Hence, it is clear that strategic material studies are essential. In this project, a stepwise strategy is proposed, moving from the synthesis of innovative chiral emissive building blocks, at the same time applicable as dopants, to conjugated polymers including these chiral monomers, and focusing on TADF as the upconversion strategy to afford strong luminescence. The synthesis efforts are combined with advanced small molecule and polymer characterization, beyond the level realized so far. Thereafter, the emissive and chiroptical properties are determined and compared to the state-of-the-art. Finally, CP-OLED devices are fabricated using the most promising materials. As such, we aim at a substantial (strategic) materials science contribution to the emergence of CP electroluminescence for high-end applications.

01 November 2025 - 31 October 2029