Study on the Ag@SiO2 enhanced the luminous intensity of the terbium complexes with benzoic acid and 1,10-phenanthroline

Five kinds of terbium complexes have been synthesized respectively with benzoic acid, 1,10-phenanthroline and 2,2'-bipyridine as ligands. The core-shell Ag@SiO2 nanocomposites was prepared. The result of transmission electron microscopy(TEM) shows the diameter of the nano-silver is about 50 nm and the thickness of the silica shell is 10, 25 and 80 nm. Combine the nanoparticles composite with terbium complexes, we explore the changes of excitation wavelength and emission intensity. The results show that: by loading the terbium complexes above the different size of nanoparticles, the excitation wavelengths of complexes do not shift, and the emission intensity of the complexes are enhanced in the presence of Ag@SiO2 nanoparticles because of metal-enhanced fluorescence (MEF), but at only a limited shell thickness particle region.