Researchers show that adding a dual-functional single-crystalline BSB-Me HTL and barrier layer can improve OLED stability

Researchers from China's Jilin University, Shenzhen University, and Tianjin University have developed a new OLED device that has a dual-functional single-crystalline layer that  serves as both an intrinsically stable hole-transporting layer (HTL) and an effective barrier layer, to improve device stability.

The material that the researchers used is 1,4-bis(4-methylstyryl)benzene (BSB-Me). The material not only serves as an effective HTL, but also exhibits desirable barrier property with a low WVTR, comparable to that of a 50-nm-thick monolayer Al2O₃ barrier layer. The researchers say that by adding this layer, highly efficient and stable single-crystal OLEDs (SC-OLEDs) can be successfully fabricated. The researchers produced a blue SC-OLEDs  that offers extended operational lifetimes (LT75) of over 1209 hours at an initial luminance of 1000 cd/m², which is notably more than thirty times enhanced compared to that of conventional OLEDs with amorphous HTLs.

Last month we reported that researchers from The University of Toyama have developed the world's first OLED that uses a non-epitaxial crystalline rubrene thin film as the emitter layer.