Dramatic improving luminous efficiency of organic light emitting diodes under low driving current using nitrogen doped hole transporter

Efficiency improvement and color optimization of white organic light-emitting diodes (WOLEDs) were achieved via employing blue host DPVBi doped with blue fluorescent, BCzVBi. The structure of high efficient WOLED device was composed of ITO/NPB/DPVBi:BCzVBi-6%/MADN:DCM2-0.5%/Bphen/Liq/Al. WOLED doped by blue fluorescent BCzVBi exhibits 6.19 cd/A of luminous efficiency and 15400 cd/m2 of maximum luminescence. It also performs 480 cd/m2 of luminance at 5.7 V and 15,400 cd/m2 at 12.9 V with CIEx,y coordinates of (0.33, 0.32) and (0.32, 0.32), respectively. Hole carrier and energy transfer from DPVBi to BCzVBi are proposed to explain the observed phenomena.

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Improving the Luminous Efficiency of Red Organic Light-Emitting Diodes Using a Carrier Balance Layer

Journal of The Electrochemical Society ◽

10.1149/1.2162458 ◽

2006 ◽

Vol 153 (3) ◽

pp. H51 ◽

Cited By ~ 8

Author(s):

Shui-Hsiang Su ◽

Meiso Yokoyama ◽

Jian-Feng Li ◽

Kao-Shing Hwang

Keyword(s):

Light Emitting Diodes ◽

Luminous Efficiency ◽

Organic Light Emitting Diodes ◽

Light Emitting ◽

Organic Light

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High-Efficiency White Organic Light-Emitting Diodes Using Blue and Red Phosphorescent Materials with Exciton Blocking Layer

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.ic29 ◽

2008 ◽

Vol 8 (9) ◽

pp. 4607-4610

Author(s):

Jung Hyun Park ◽

Ji Hoon Seo ◽

Ji Hyun Seo ◽

Seok Jae Lee ◽

Ja Ryong Koo ◽

...

Keyword(s):

High Efficiency ◽

Light Emitting Diodes ◽

Blue Emission ◽

Luminous Efficiency ◽

Organic Light Emitting Diodes ◽

Blocking Layer ◽

Maximum Luminance ◽

Red Emission ◽

Light Emitting ◽

Organic Light

High-efficiency white organic light-emitting diodes (WOLEDs) were fabricated with two emissive layers and an exciton blocking layer (EBL) was sandwiched between two phosphorescent dyes, bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl) iridium III (FIrpic) as the blue emission and iridium(III) bis(5-acetyl-2-phenylpyridinato-N,C2′) acetylacetonate ((acppy)2Ir(acac)) as the red emission. This EBL effectively prevented a triple–triple energy transfer between the two phosphorescent emissive layers with blue and red emission. The white device showed Commission Internationale De L'Eclairage (CIEx,y) coordinates of (0.33, 0.42) at 22400 cd/m2, a maximum luminance of 27300 cd/m2 at 13.2 V, and a maximum luminous efficiency of 26.9 cd/A.

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The Effects of Two Spacers on White Organic Light-Emitting Diodes

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.ic72 ◽

2008 ◽

Vol 8 (9) ◽

pp. 4584-4587 ◽

Cited By ~ 1

Author(s):

Ji Hoon Seo ◽

Jun Ho Kim ◽

Woo Young Kim ◽

Kum Hee Lee ◽

Seung Soo Yoon ◽

...

Keyword(s):

Light Emitting Diodes ◽

Luminous Efficiency ◽

Organic Light Emitting Diodes ◽

Light Emitting ◽

Highly Efficient ◽

Organic Light

The authors have demonstrated highly efficient white organic light-emitting diodes (WOLEDs) by using two emissive materials as a dopant, 1,4-Bis[2-(4′-diphenylaminobiphenyl-4-yl)vinyl]benzene (DABPV-ph) and iridium(III) bis(5-acetyl-2-phenylpyridinato-N,C2′) acetylacetonate ((acppy)2Ir (acac)). In these WOLEDs, 2-methyl-9,10-di(2-naphthyl)anthracene (MADN), and 4,4′-N,N′-dicarbazole-biphenyl (CBP) were used as a spacer among the three emissive layers. The maximum luminous efficiency of the three devices with no spacer, MADN and CBP as a spacer were 11.50, 8.32, and 25.70 cd/A at 0.08, 12.7, and 0.01 mA/cm2 and the Commission Internationale De L'Eclairage (CIEx,y) coordinates were (x = 0 21, y = 0.34), (x = 0.21, y = 0.34), and (x = 0.33, y = 0.33) at 11 V, respectively.

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