Hydroxyphenyl-pyridine beryllium complex (Bepp(2)) as a blue electroluminescent material

A novel blue luminescent chelate complex Bepp(2) (pp = 2-(2-hydroxyphenyl)pyridine) was synthesized as an electroluminescent material. The single-crystal X-ray diffraction study showed that there are intermolecular pi. ..pi interactions in the solid state of Bepp(2). This structural character can facilitate charge transport ability. The photoluminescence and electroluminescence properties of Bepp(2) were characterized. Bepp(2) exhibits very strong photoluminescence at 440 nm in chloroform solution. Its PL quantum yield is 80% higher than that of Alq(3) in solution. In this paper we report that Bepp(2) can be used as an emitting material to fabricate blue light electroluminescent devices. The devices with the configuration of [ITO/Cu-Pc/TPD/Bepp(2)/LiF/Al] show electroluminescent efficiency up to 0.55 lm/W. Bepp(2) shows blue EL emission centered at 450 nm. We also demonstrated that Bepp(2) can be used as host material to prepare orange-red EL devices. For the devices of [ITO/TPD/DCM (2wt%) doped Bepp(2)/Al], orange-red color light was observed.