N1,N1,N3,N3-tetra([1,1′-biphenyl]-4-yl)-N5,N5-diphenylbenzene-1,3,5-triamine: Synthesis, optical properties and application in OLED devices as efficient hole transporting material

•A hole transporting material was synthesized and characterized.•The compound exhibits high hole mobility and excellent thermal stability.•The resulting device exhibits higher efficiency compared with NPB-device.

A hole-transporting material, N1,N1,N3,N3-tetra([1,1′-biphenyl]-4-yl)-N5,N5-diphenylbenzene-1,3,5-triamine (TDAB-BP), was synthesized by di([1,1′-biphenyl]-4-yl)amine and 3,5-dichloro-N,N-diphenylaniline via Buchwald–Hartwig coupling reaction. The material exhibit high hole mobility, excellent thermal and morphological stability. TDAB-based OLED device exhibited the highest performance in terms of the maximum current efficiency (9.34 cd/A), maximum power efficiency (5.89 lm/W), and maximum external quantum efficiency (6.61%), which is significantly improved than that of the standard device based on 4,4′-bis[N-(1-naphthyl)-N-phenyl-amino]-biphenyl (NPB) (7.12 cd/A, 4.90 lm/W and 5.31%). Furthermore, TDAB-BP shows a higher decomposition temperature (Td) of 505 °C than that of NPB (418 °C). This material could be a promising hole-transporting material, especially for the high-temperature applications of OLEDs and other organic electronic devices.

Graphical abstractA hole-transporting material TDAB-BP was synthesized, which exhibits high hole mobility, excellent thermal and morphological stability. Blue OLED device based on TDAB-BP exhibits high performance with the maximum current efficiency of 9.34 cd/A, maximum power efficiency of 5.89 lm/W and maximum external quantum efficiency of 6.61%. TDAB-BP could significantly improve the device performance than traditional NPB.Figure optionsDownload full-size imageDownload as PowerPoint slide