High-efficient white organic light-emitting diodes using the two different blue fluorescent emitters

Area of Science:

• Materials Science
• Organic Electronics
• Photophysics

Background:

• White organic light-emitting diodes (WOLEDs) are crucial for next-generation displays and lighting.
• Developing efficient and stable blue emitters remains a key challenge in WOLED technology.

Purpose of the Study:

• To demonstrate high-efficiency WOLEDs utilizing novel blue fluorescent emitters.
• To investigate the performance enhancement of WOLEDs through structural optimization.

Main Methods:

• Fabrication of WOLEDs incorporating two blue fluorescent emitters: 4"-(2,2-diphenylvinyl)-1-[4-(N,N-diphenylamino)-styryl]-terphenyl (PVAS-tPh) and 1,4-Bis[2-(7-N-diphenyamino-2-(9,9-diethyl-9H-fluoren-2-yl)) vinyl] benzene (DAF-ph).
• Integration of red and green phosphorescent emitters: bis(5-benzoyl-2-phenylpyridinato-C,N)iridium(III) (acetylacetonate) ((Bzppy)1Ir(III)acac) and fac-tris(2-phenypyridine) iridium(III) (Ir(ppy)3).
• Device structural optimization to enhance performance metrics.

Main Results:

• The optimized WOLED device exhibited a 2.3-fold increase in power efficiency compared to the control device.
• Achieved a maximum luminance of 36300 cd/m² at 13 V.
• Attained a maximum power efficiency of 32.2 lm/W at a current density of 0.017 mA/cm².

Conclusions:

• The strategic combination of novel blue fluorescent emitters and phosphorescent emitters enables high-efficiency WOLEDs.
• Structural optimization is a critical factor in maximizing the performance of WOLED devices.
• The demonstrated WOLEDs show significant potential for advanced lighting and display applications.