The Performance of White Light OLED Phosphorescence Materials

Abstract:

High-efficiency WOLEDs based on phosphorescent dye bis[2-(4-tert-butylphenyl)benzothiazolato-N,C2′]iridium (acetylacetonate) [(t-bt)2 lr (acac)] as yellow emitting layer were fabricated. The turn-on voltage of the device was 3 V with a maximum luminance of 15,460 cd/m2 at 16.5 V and a maximum luminance efficiency of 7.5 lm/W at 4 V. The CIE coordinates located at (0.33, 0.32) and remained unchanged at over 8 V, almost consistent with optimum the white CIE of (0.33, 0.33). The effect of carrier trapping and energy transfer on the device performance was also discussed.

• Periodical: Advanced Materials Research (Volumes 512-515)
• Pages: 1807-1812
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.512-515.1807
• Online since: May 2012
• Authors: Zi Jun Yao, Hua Jing Zheng, Zheng Ruan, Quan Jiang
• Keywords: CIE Coordinates, Organic Light Emitting Diode, Phosphorescent Materials, White Light

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