Constructing high-performance blue, yellow and red electroluminescent devices based on a class of multifunctional organic materials

Two new indolo[3,2-b]carbazole derivatives (DPDT-ICZ and DNDT-ICZ) with multifunctionality were designed and synthesized. They were employed as deep-blue emitters, hole-transporting materials and hosts to fabricate organic light-emitting devices (OLEDs). The devices which used them as emitters displayed deep-blue emissions with CIE coordinates of (0.15, 0.08). They have been employed as hole-transporting and host material simultaneously to construct high performance yellow and red phosphorescent OLEDs. High power efficiencies (78.3 lm W−1 for yellow devices and 20.4 lm W−1 for red devices) for phosphorescent OLEDs were achieved. Importantly, these devices displayed the feature of low roll-off of efficiencies. At the luminance of 1000 cd m−2, roll-off of current efficiencies was 1.3% for the yellow device and 14.6% for the red device.