Enhancement of electroluminescent properties of organic optoelectronic integrated device by doping phosphorescent dye**Project supported by the National Natural Science Foundation of China (Grant No. 61675041) and the National Science Funds for Creative Research Groups of China (Grant No. 61421002).

Abstract

Organic optoelectronic integrated devices (OIDs) with ultraviolet (UV) photodetectivity and different color emitting were constructed by using a thermally activated delayed fluorescence (TADF) material 4, 5-bis(carbazol-9-yl)-1, 2-dicyanobenzene (2CzPN) as host. The OIDs doping with typical red phosphorescent dye [tris(1-phenylisoquinoline)iridium(III), Ir(piq)3], orange phosphorescent dye {bis[2-(4-tertbutylphenyl)benzothiazolato-N, C2′]iridium (acetylacetonate), (tbt)2Ir(acac)}, and blue phosphorescent dye [bis(2, 4-di-fluorophenylpyridinato)-tetrakis(1-pyrazolyl)borate iridium(III), FIr6] were investigated and compared. The (tbt)2Ir(acac)-doped orange device showed better performance than those of red and blue devices, which was ascribed to more effective energy transfer. Meanwhile, at a low dopant concentration of 3 wt.%, the (tbt)2Ir(acac)-doped OIDs showed the maximum luminance, current efficiency, power efficiency of 70786 cd/m2, 39.55 cd/A, and 23.92 lm/W, respectively, and a decent detectivity of 1.07 × 1011 Jones at a bias of −2 V under the UV-350 nm illumination. This work may arouse widespread interest in constructing high efficiency and luminance OIDs based on doping phosphorescent dye.