Synthesis and luminescence properties of salicylaldehyde isonicotinoyl hydrazone derivatives and their europium complexes

• Four novel europium complexes have been prepared and characterized.
• All the europium complexes exhibited characteristic emissions of europium ion.
• The luminescence intensity of the synthesized target complexes has been discussed.
• The europium complexes possessed relatively good fluorescence quantum yields.
• The electrochemical properties of the target complexes have been estimated.

Four novel salicylaldehyde isonicotinoyl hydrazone derivatives and their corresponding europium ion complexes were synthesized and characterized, while the luminescence properties and the fluorescence quantum yields of the target complexes were investigated. The results indicated that the ligands favored energy transfers to the emitting energy level of europium ion, and four target europium complexes showed the characteristic luminescence of central europium ion. Besides the luminescence intensity of the complex with methoxy group, which possessed the highest fluorescence quantum yield (0.522), was stronger than that of other complexes. Furthermore, the electrochemical properties of the target complexes were further investigated by cyclic voltammetry, the results indicated that the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) energy levels and the oxidation potential of the complexes with electron donating group increased, however, that of the complexes with accepting electron group decreased.

Four novel salicylaldehyde isonicotinoyl hydrazone derivatives and their corresponding europium complexes were synthesized and characterized. The results indicated that all the complexes exhibited characteristic emissions of europium ion. The relationship between the structure of ligands and luminescence intensity of the europium complexes has been discussed.Figure optionsDownload as PowerPoint slide