A new blue-green light-emitting iridium(Ⅲ) bis(1-phenylpyridine)(1

2

4-triazole pyridine)complex was synthesized by the reaction of 1-phenylpyridine

1

2

4-triazole pyridine and iridium trichloride hydrate

which expanded the choice range of blue-light iridium complexes effectively.Most of multilayer phosphorescent devices which have been reported before were fabricated by high vacuum thermal evaporation.In this paper

polyvinylcarbazole(PVK)was used as polymer host by comparing the spectra overlap degree of photoluminescent(PL)emission spectrum of the host polymer(PVK and polyfluorene)and the absorption spectra of the iridium complex.Single-layer polymer blends structures are advantageous because they can be fabricated by solution processing at room temperature.Different concentration of iridium complex guest was doped into PVK host.PL spectra in solid film state weren't the same as those in solution state.Energy transfer from host to guest in solution state wasn't completely comparing with that in solid film state.Because F rster and Dexter energy transfer could be happened at the same time in solid film state.While in solution state

the distance of intermolecule is becoming farther

Dexter energy transfer couldn't be happened.With the increase of doping concentration

the intensity of PL emission peak of complex increased gradually.The structure of the complex was characterized by elemental analysis

1

HNMR

and liquid-mass spectroscopy.The UV-Vis spectrum

photoluminescence spectrum and photoluminescence efficiency were investigated.Electroluminescence(EL)device was fabricated when the complex guest of 2% was doped into polymer host PVK.The UV-Vis spectrum showed the absorption peaks below 350nm are attributed to the spin-allowed single state

1

π-π

*

transition of cyclometalated ligands.The complex also gives rise to a strong photoluminescence at 470 nm at room temperature under photo excitation.Compared to the photoluminescence spectrum

a red-shifted of emission was observed from the electroluminescence spectrum.This maybe resulted from the congregation of small-molecule guest or the formation of excimer.The reason of red-shift of EL spectra is in progress.