Synthesis, crystal structure and blue electroluminescence of a new zinc complex based on 2,6-bis(benzimidazolyl)pyridine

A very stable and blue luminescent complex Zn(bbp)Cl2 (bbp: 2,6-bis(benzimidazolyl)pyridine) was synthesized. X-ray crystal structural analysis for the complex revealed that there are intermolecular π⋯π interactions in the solid state. The fluorescence properties for this complex were studied. The similar devices with the structure of [ITO/CuPc(31 nm)/NPB(80 nm)/[Zn(bbp)Cl2] (or L) (85 nm)/LiF15/Al] were constructed to investigate their electroluminescent performance. Both the complex and the ligand can be fabricated as blue-emitting materials. The complex shows emission peak at 555 nm, electroluminescent efficiency 0.017 cd A−1 and turn-on voltage 7 V, compared to 470 nm, 0.036 cd A−1 and 9 V for the ligand.