Photoluminescent properties of novel Y(III), Sm(III), Eu(III), Gd(III) and Tb(III) complexes with 2-(1H-1,2,4-Triazol-3-yl)pyridine

Abstract

2-(1H-1,2,4-Triazol-3-yl)pyridine was investigated as suitable ligand for the preparation of new Y(III), Sm(III), Eu(III), Gd(III) and Tb(III) complexes. Elemental analysis, mass spectrometry, thermal analysis, FT-IR and P-XRD methods were used to investigate their structural configuration. All the prepared complexes are highly luminescent, having an impressive visual emission under UV excitation. Fluorescence spectroscopy revealed in case of Sm(III), Eu(III) and Tb(III) complexes intense metal centered specific narrow band emissions from the f–f transitions within 4f orbitals, while in case of Gd(III) and Y(III) complexes intense wide band emissions were recorded most probable due the heavy atom effect over the excited intraligand states. The excitation peaks are conveniently located in UV-A region for all prepared complexes apart from Sm(III) complex where the excitation peak is located within the violet region of the spectrum. The remarkable luminescent properties might recommend these complexes for applications in optical devices, as photonic conversion media.