A series of high efficiency yellow devices with double-emitting layers were fabricated by selecting bis(2-phenylquinoline)(2,2,6,6-tetramethylheptane-3,5-dionate)iridium(Ⅲ)(PQ2Ir(dpm)) and tris(phenylpyrazole) iridium (Ir(mppy)3) as phosphorescent materials,and 4,4′,4″-tri(9-carbazoyl)triphenylamine (TcTa) and 2,6-bis(3-(9H-carbazol-9-yl)phenyl)pyridine (26DCzPPy) as host materials,respectively.The effects on the efficiency and spectrum of yellow light devices were investigated by optimizing the doping concentration of the red phosphorescent material.Finally,the optimized device with turn-on voltage,the maximum brightness,current efficiency power efficiency and external quantum efficiency up to 3.5V,147900cd/m2,88.91cd/A,61.05lm/W and 33.2%,respectively,was obtained.Even at the practical brightness of 1000cd/m2,current efficiency and external quantum efficiency as high as 84.9cd/A and 32.1%,respectively,can still be retained.
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基金资助
吉林省发改委项目(2017C050);吉林省科技厅项目(20190302001GX)
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