Synthesis and electroluminescent property of ternary complexes Eu(TTA)3M

Three kinds of rare earth ternary complexes of Eu3+ with HTTA and M (M = 5-NO2Phen, 2,2′-Dipy and TPPO) have been synthesized and characterized using various spectral techniques such as elemental analysis, TGA-DTA, IR, UV and fluorescent. Results show that the complexes of Eu(III) emit strong red luminescence when excited by UV light. The complex Eu(TTA)35NO2Phen posses the highest sensitized luminescent efficiency and the longest lifetime in the studied complexes. TG curves indicate that Eu(TTA)35NO2Phen is most stable. In device ITO/PVK/Eu(TTA)35NO2Phen/Al, Eu3+ may be excited by intramolecular energy transfer from ligands as observed by electroluminescence. The main emitting peak at 614 nm can be attributed to the transition of 5D0 → 7F2 of Eu3+ ion, and this process results in the enhancement of red emission from electroluminescence device.