Anthracene Green Fluorescent Derivatives Based on Optimized Side Groups for Highly Efficient Organic Light-Emitting...

Area of Science:

• Organic electronics
• Materials science
• Photophysics

Background:

• Anthracene and diphenylamine derivatives are crucial in organic light-emitting diodes (OLEDs).
• Developing efficient green fluorescent emitters is key for advanced display technologies.

Purpose of the Study:

• To synthesize and characterize two novel green fluorescent materials: N,N,N',N'-Tetra-o-tolyl-anthracene-9,10-diamine (o-Me-TAD) and N,N'-bis(2,5-dimethylphenyl)-N,N'-di-o-tolylanthracene-9,10-diamine (DMe-o-Me-TAD).
• To evaluate their performance as dopants in OLED devices.

Main Methods:

• Synthesis of o-Me-TAD and DMe-o-Me-TAD via Buchwald-Hartwig amination.
• Photoluminescence (PL) spectroscopy to determine emission wavelengths.
• Fabrication and characterization of doped OLED devices to measure electroluminescence (EL) properties, current efficiency (CE), and external quantum efficiency (EQE).

Main Results:

• Both o-Me-TAD and DMe-o-Me-TAD exhibit strong green fluorescence in solution (PL max at 518 nm and 520 nm, respectively).
• Doped devices using DMe-o-Me-TAD achieved higher CE (22.37 cd/A) and EQE (7.02%) without roll-off compared to o-Me-TAD (CE: 19.78 cd/A, EQE: 5.97%).
• EL peaks for the doped devices were observed at 522 nm and 523 nm, with corresponding CIE coordinates indicating pure green emission.

Conclusions:

• The synthesized anthracene-diphenylamine derivatives, o-Me-TAD and DMe-o-Me-TAD, are effective green fluorescent dopants for OLEDs.
• DMe-o-Me-TAD demonstrates superior performance, offering high efficiency and no roll-off, making it a promising candidate for display applications.