Acta Phys. -Chim. Sin. ›› 2016, Vol. 32 ›› Issue (5): 1273-1281.doi: 10.3866/PKU.WHXB201602193

• ARTICLE • Previous Articles     Next Articles

Synthesis of Solution-Processable Propeller-Shaped Oligomers Based on Trinaphthylbenzene and Their Application in Blue Organic Light-Emitting Diodes

Zeng-Ze CHU1,Dan WANG2,Hong-Wei WU2,De-Chun ZOU2,*()   

  1. 1 College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang 110034, P. R. China
    2 Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
  • Received:2015-11-12 Published:2016-05-07
  • Contact: De-Chun ZOU E-mail:dczou@pku.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(50833001);National Key Basic Research Program of China (973)(2011CB933300);Research Starting Foundation for Doctoral Program of Shenyang Normal University, China(054-55440109013)

Abstract:

Although considerable improvements have been achieved in novel materials and device architectures for organic light-emitting diodes (OLEDs), great challenges remain in efficiency, color purity, and stability for blue emitters because of their intrinsic wide band-gap. In this study, trinaphthylbenzene (TNB), a propeller-shaped conjugated system, is employed as the central moiety for the construction of the organic lightemitting materials. Its nonplanar propeller-shaped structure and easy chemical modification are beneficial for building three-dimensional (3D) π-π conjugated systems to suppress aggregates and excimers. We have demonstrated a facile approach for the synthesis of a set of propeller-shaped blue-emitting oligomers based on the TNB core with peripheral units of naphthalene, anthracene or triphenylamine via the combination of SiCl4-catalyzed cyclotrimerization and Suzuki coupling reactions. The thermal, optical, and electrochemical properties of the materials were investigated. The results indicate that the naphthalene and triphenylamine substituted oligomers, 1, 3, 5-tris(3-(1-methoxynaphthalen-2-yl)-4-methoxynaphthalen-1-yl)benzene (TNNB) and 1, 3, 5-tris (3-(4-(N, N-diphenylamino)phenyl)-4-methoxynaphthalen-1-yl) benzene (TPANB), have the best thermal stability. They exhibit deep blue photoluminescence (PL) emission at 382 and 415 nm in solution, respectively. In comparison with the solution spectra, the emission spectra in films show only a very slight red-shift of 1 nm for TNNB and a blue-shift of 6 nm for TPANB. The electroluminescent device fabricated using TNNB as the emitter has a pure blue emission with a brightness of 5273 cd·m-2 and Commission Internationale de L′Eclairage (CIE) coordinates of (0.17, 0.11).

Key words: Trinaphthylbenzene, Cyclotrimerization reaction, Blue-emitting, Propeller-shaped, Organic light-emitting diode

MSC2000: 

  • O644