Synthesis and characterization of terbium(III)-pyromellitic acid (H4L)-1,10-phenanthroline (phen) luminescent complex

The terbium(III)-pyromellitic acid(H4L)-1,10-phenanthroline(phen) luminescent complex was synthesized using a co-precipitation method. The chemical composition of the synthesized complex was speculated to be Tb4L3(phen)0.075·10H2O by elemental analysis, inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and Fourier-transform infrared spectroscopy (FT-IR). The X-ray diffraction analytic results indicated that the synthesized complex is a new crystalline complex, whose structure was different from those of other two ligands. The scanning electron microscopy analytic results showed that the product was of spherical crystals with good dispersion property, and the mean diameter of the spheres was about 1-2 μm. The TG-DTA result showed that the complex had good stability below 489 °C. PL spectra showed that the complex emitted characteristic green fluorescence of Tb(III) ion under ultraviolet excitation.