Yellow organic light-emitting devices (YOLEDs) with a novel structure of ITO/MoO 3 (5 nm)/NPB(40 nm)/ TCTA(15 nm)/CBP:(tbt) 2 Ir(acac)(x%)(25 nm)/FIrpic(y nm)/TPBi(35 nm)/Mg:Ag are fabricated. The ultrathin blue phosphorescent bis [(4,6-difluorophenyl)-pyridi-nato-N,C2 ](picolinate) iridium (III) (FIrpic) layer is regarded as a highperformance modification layer. By adjusting the thickness of FIrpic and the concentration of (tbt) 2 Ir(acac), a YOLED achieves a high luminance of 41618 cd/m 2 , power efficiency of 49.7 lm/W, current efficiency of 67.3 cd/A, external quantum efficiency (EQE) of 18%, and a low efficiency roll-off at high luminance. The results show that phosphorescent material of FIrpic plays a significant role in improving YOLED performance. The ultrathin FIrpic modification layer blocks excitons in EML. In the meantime, the high triplet energy of FIrpic (2.75 eV) alleviates the exciton energy transport from EML to FIrpic.

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(1phenylisoquinoline)iridium(III), Ir(piq) 3 ], orange phosphorescent dye {bis[2-(4-tertbutylphenyl)benzothiazolato-N, C 2 ]iridium (acetylacetonate), (tbt) 2 Ir(acac)}, and blue phosphorescent dye [bis(2, 4-di-fluorophenylpyridinato)-tetrakis(1pyrazolyl)borate iridium(III), FIr6] were investigated and compared. The (tbt) 2 Ir(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) 2 Ir(acac)-doped OIDs showed the maximum luminance, current efficiency, power efficiency of 70786 cd/m 2 , 39.55 cd/A, and 23.92 lm/W, respectively, and a decent detectivity of 1.07 × 10 11 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.