Efficient Bipolar Blue AlEgens for High-Performance Nondoped Blue OLEDs and Hybrid White OLEDs

摘要

Blue organic luminescent materials play a crucial role in full-color display and white lighting but efficient ones meeting commercial demands are very rare. Herein, the design and synthesis of tailor-made bipolar blue luminogens with an anthracene core and various functional groups are reported. The thermal stabilities, photophysical properties, electronic structures, electrochemical behaviors, carrier transport abilities, and electroluminescence performances are systematically investigated. The luminogen TPE-TAPBI containing a tetraphenylethene moiety shows aggregation-induced emission, while another luminogen TriPE-TAPBI bearing a triphenylethene unit exhibits light aggregation-caused quenching. In comparison with TriPE-TAPBI, TPE-TAPBI has stronger blue emission in neat film and functions more efficiently in nondoped organic light-emitting diodes (OLEDs). High maxima current, power, and external quantum efficiencies of 7.21 cd A(-1), 6.78 lm W-1, and 5.73%, respectively, are attained by the nondoped blue OLED of TPE-TAPBI (CIEx,y = 0.15, 0.16). Moreover, efficient two-color hybrid warm white OLEDs (CIEx,y = 0.457, 0.470) are achieved using TPE-TAPBI neat film as the blue-emitting component, which provide total current, power, external quantum efficiencies of up to 70.5 lm W-1, 76.0 cd A(-1), and 28% at 1000 cd m(-2), respectively. These blue and white OLEDs are among the most efficient devices with similar colors in the literature.