Small organic molecules with finely tunable physical properties are highlyd esired for the fabricationo fl owcost and high-performance organic electronic devices.Int his work, the syntheses of as eries of T-shaped NBN-embedded dibenzophenalene derivatives throught he formationo fa key brominated intermediate in as toichiometrically controlled reactiona re presented. The geometrica nd electronic structures of these T-shaped molecules can be simply tailored by attaching substituents along the direction perpendicular to the molecular main backbones,r esulting in desirable physical properties, such as high thermals tability with a decomposition temperature of more than 350 8C, and intensive blue luminescence with aq uantum yield up to 0.62. Organic light-emitting diode devices fabricated with such moleculesa st he emittingl ayer release pure blue light with CIE (0.16,0 .12).

Random-bowls textured (RBT) optical film with high optical haze (∼96%) possessing strong scattering ability is attached directly to the glass substrate exterior of organic light-emitting diodes (OLEDs) in order to improve the light-extraction efficiency of the OLEDs. The power and current efficiency of OLEDs with RBT film are improved by 27.2% and 26.3%, respectively, compared with the reference OLED without RBT film. Additionally, the EL spectrum of the OLEDs remains stable with the usage of the RBT optical film and change of visual angle. We confirm that the optical film can change the light traveling path due to its random-bowls structure and improve the extraction of a part of the light confined into the substrate by ray-tracing optical simulation. The utilization of RBT optical film with high haze is a simple and promising approach to enhancing light-extraction efficiencies of OLEDs.

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In this study, we have synthesized the molybdenum sulfide quantum dots (MoS2 QDs) and zinc sulfide quantum dots (ZnS QDs) and demonstrated a highly efficient green phosphorescent organic light-emitting diode (OLED) with hybrid poly (3,4-ethylenedioxythiophene)/poly (styrenesulfonate) (PEDOT:PSS)/QDs hole injection layer (HIL). The electroluminescent properties of PEDOT:PSS and hybrid HIL based devices were explored. An optimized OLED based on the PEDOT:PSS/MoS2 QDs HIL exhibited maximum current efficiency (CE) of 72.7 cd A−1, which shows a 28.2% enhancement as compared to counterpart with single PEDOT:PSS HIL. The higher device performance of OLED with hybrid HIL can be attributed to the enhanced hole injection capacity and balanced charge carrier transportation in the OLED devices. The above analysis illustrates an alternative way to fabricate the high efficiency OLEDs with sulfide quantum dots as a HIL.

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