Studies On The Synthesis And Photoluminescence Property Of The Novel Bis-Schiff Base Metal Complexes

Recently, more and more organic electroluminescence devices were used in the flat panel display field because of the low energy consume and the excellent luminescent properties. Many interests have also been paid to the research of organic luminescent materials. Among the luminescent materials, the metal complexes with bis-schiff base as ligand could be a kind of excellent luminescent materials because they can fit with the conditions of charge balance and saturated coordination number.In this paper, a series of research were carried out in order to get a kind of good compounds with high fluorescence efficiency and tunable wavelength.First, a pair of bis-schiff base ligands, salicylidene ethylenediamine (L₁) and N, N'-dibenzoyl ethylenediamine (L₂)_, were prepared by direct synthesis method. The synthesized compounds were approved to be pure phase by elemental analysis, NMR and IR. The weak blue emission can be found from the fluorescence spectrum of the bis-schiff base ligands of the L₁ and L₂. The L₁ ligand and transition metal ions Zn²⁺ can be formed complexes Zn (L₁)₂ with good emission property. Both Zn²⁺ and Eu³⁺ could react with the L2 liangd to form metal complexes. While the former is the central atom perturbation complexes ligand emitting Zn (L₂) 2 and the latter is the ligand perturbation of the central atom emitting complexes Eu (L₂) 3.Through a variety of research of two-ligand complexes, L2 and 8-hydroxyquinoline with metal ions Zn²⁺ can form a kind of double-ligand complexes with tunable wavelength and strong emission. The luminescent intensity of single-ligand complex of Eu3+ with benzoic acid can be increased with a little of L2 was introduced in the reaction system.