Fluorene–Triphenylamine-Based Bipolar Materials: Fluorescent Emitter and Host for Yellow Phosphorescent OLEDs

Ramanaskanda Braveenth; Hasu Jung; Keunhwa Kim; Bo Mi Kim; Il-Ji Bae; Miyoung Kim; Kyu Yun Chai

doi:10.3390/app10020519

Fluorene–Triphenylamine-Based Bipolar Materials: Fluorescent Emitter and Host for Yellow Phosphorescent OLEDs

Applied Sciences ◽

10.3390/app10020519 ◽

2020 ◽

Vol 10 (2) ◽

pp. 519

Author(s):

Ramanaskanda Braveenth ◽

Hasu Jung ◽

Keunhwa Kim ◽

Bo Mi Kim ◽

Il-Ji Bae ◽

...

Keyword(s):

Light Emitting Diode ◽

Light Emitting ◽

Organic Light Emitting Diode ◽

Organic Light ◽

Maximum Current ◽

Better Than

In this study, two new bipolar materials were designed and synthesized: N1-(9,9-diphenyl-9H-fluoren-2-yl)-N1-(4,6-diphenylpyrimidin-2-yl)-N4,N4-diphenylbenzene-1,4-diamine (FLU-TPA/PYR) and N1-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-N1-(9,9-diphenyl-9H-fluoren-2-yl)-N4,N4 diphenylbenzene-1,4-diamine (FLU-TPA/TRZ). We fabricated two different devices, namely a yellow phosphorescent organic light-emitting diode (PhOLED) and a non-doped fluorescent OLED emitter with both FLU-TPA/PYR and FLU-TPA/TRZ. The FLU-TPA/PYR host-based yellow PhOLED device showed better maximum current, power and external quantum efficiencies at 21.70 cd/A, 13.64 lm/W and 7.75%, respectively. The observed efficiencies were better than those of the triazine-based FLU-TPA/TRZ. The non-doped fluorescent device with the triazine-based FLU-TPA/TRZ material demonstrated current, power and external quantum efficiencies of 10.30 cd/A, 6.47 lm/W and 3.57%, respectively.

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Optimal Color Stability for White Organic Light-Emitting Diode (WOLED) by Using Multiple-Ultra-Thin Layers (MUTL)

International Journal of Photoenergy ◽

10.1155/2013/173289 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Kan-Lin Chen ◽

Chien-Jung Huang ◽

Wen-Ray Chen ◽

Fong-Yi Lin ◽

Teen-Hang Meen ◽

...

Keyword(s):

Light Emitting Diode ◽

Color Stability ◽

Thin Layers ◽

Slight Variation ◽

Light Emitting ◽

Organic Light Emitting Diode ◽

Glass Substrates ◽

Organic Light ◽

Ito Glass ◽

Better Than

The work demonstrates the improvement of color stability for white organic light-emitting diode (WOLED). The devices were prepared by vacuum deposition on ITO-glass substrates. These guest materials of 5,6,11,12-tetraphenylnaphthacene (Rubrene) were deposited in 4,4′-bis(2,2-diphenyl vinyl)-1,1′-biphenyl (DPVBi), resulting in an emitting layer. Experimental results reveal that the properties in the multiple-ultra-thin layer (MUTL) are better than those of the emitting layer with a single guest material, reaching the commercial white-light wavelength requirement of 400–700 nm. The function of the MUTL is as the light-emitting and trapping layer. The results show that the MUTL has excellent carrier capture effect, leading to high color stability of the device at various applied voltages. The Commissions Internationale De L’Eclairage (CIE) coordinate of this device at 3~7 V is few displacement and shows a very slight variation of (0.016, 0.009). The CIE coordinates at a maximal luminance of 9980 cd/m2are (0.34, 0.33).

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