Lighting up the future: a breakthrough in blue OLED technology

Organic light-emitting compounds (OLEDs) are now used in display screens and lighting sources because of their rich color range, easy fabrication, and flexibility. However, achieving high-efficiency blue emission remains a challenge, as improvements in energy efficiency often compromise color purity. Ge et al. investigated advanced materials that leverage multiple energy transfer mechanisms to enhance both brightness and efficiency while preserving deep-blue color quality.

The material, a hybridized local and charge-transfer (HLCT) emitter, PBOAn₂N, simultaneously achieves deep-blue emission and a high external quantum efficiency of 9.7% with remarkably low efficiency roll-off, a standard decrease in efficiency most OLEDs experience at high brightness. In the study, PBOAn₂N demonstrates dual functionality, acting as an efficient emitting layer and an excellent host for phosphors. This dual capability enables the fabrication of two-color hybrid white OLEDs when the deep-blue PBOAn₂N is combined with orange emitters, with a record-high color rendering index of 68.4 and minimal efficiency roll-off, representing a significant advancement over previous HLCT systems for next-generation display and lighting applications.

“PBOAn₂N demonstrates a feasible path to creating high-quality white light from a simple architecture,” said author Junsheng Yu.

The team synthesized PBOAn₂N using Suzuki cross-coupling and confirmed its molecular structure and behavior. OLED devices based on the PBOAn₂N were fabricated via thermal evaporation in vacuum, and key metrics such as efficiency, brightness, color coordinates, and roll-off were measured.

Despite the promising results, PBOAn₂N cannot yet be used in commercial applications. The team plans to test their device’s stability under real-world electrical conditions, optimize the architecture to accommodate three-color systems, and further examine the electronic mechanisms behind the material’s behavior.

Source: “High-performance non-doped deep-blue/white OLEDs via HLCT-type oxazole emitter with negligible efficiency roll-off,” by Xin Ge, Qiao Luo, Huixia Xu, Hua Wang, Ding Zheng, Junsheng Yu, Applied Physics Letters (2025). The article can be accessed at https://doi.org/10.1063/5.0288801 .