Solution-processed white phosphorescent tandem organic light-emitting devices.

Area of Science:

• Materials Science
• Organic Electronics
• Device Physics

Background:

• Organic light-emitting diodes (OLEDs) are crucial for modern displays and lighting.
• Achieving high efficiency and low-cost manufacturing for large-area applications remains a challenge.

Purpose of the Study:

• To develop highly efficient, solution-processed phosphorescent tandem OLEDs.
• To demonstrate the potential for printable, low-cost, and large-area white lighting.

Main Methods:

• Fabrication of inverted phosphorescent tandem OLEDs using solution-processing techniques.
• Characterization of device efficiency (cd A⁻¹) and external quantum efficiency (EQE) at high luminance.

Main Results:

• Achieved 94 cd A⁻¹ and 26% EQE at 5000 cd m⁻² for green phosphorescent devices.
• Achieved 69 cd A⁻¹ and 28% EQE at 5000 cd m⁻² for white phosphorescent devices.
• Demonstrated high performance with an inverted device structure.

Conclusions:

• Solution-processed phosphorescent tandem OLEDs offer a viable path to high-efficiency lighting.
• The developed technology enables printable, cost-effective, and large-area white lighting solutions.