Improved Photoluminescence Properties of Ternary Terbium Complexes in Mesoporous Molecule Sieves

Abstract

Ternary terbium complexes were fully encapsulated and uniformly distributed into the channels of unmodified and modified mesoporous molecule sieves of SBA-15 and characterized by transmission electron micrographs (TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-vis) absorption spectra, inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and elemental analysis. The luminescent properties for the encapsulated complexes were systematically studied in contrast to the pure complexes, including excitation and emission spectra, fluorescence dynamics, photostability under UV exposure, and the temperature dependence of intensity and lifetime. The results indicate that the excitation bands assigned to the pi-pi* electron transition of the ligands for Tb complexes encapsulated in SBA-15 were split into different components due to decreased symmetry and disappeared at long wavelengths. Owing to suppressed vibration transitions, the outer quantum efficiency of the 5D4-7FJ (J = 0-5) emissions was enhanced largely in comparison to the pure complexes. In addition, the photostability and thermostability of the emissions were also improved considerably.

Photoluminescence properties of terbium complexes bound to amorphous silica

“…Comparison with literature data on terbium PL lifetimes measured with various terbium complexes covalently grafted to silica-based materials i.e. τ = 338-745 μs [24], 1528 μs [25], 690 μs [26] or 900 μs [27] is supportive for a reduced non-radiative quenching of terbium emission in our materials.…”

Oxygen-sensing materials based on [Ru(bpy)3]2+ covalently grafted MSU-3 mesoporous molecular sieves

“…The Ru(II) simply physisorbed sample (D) shows obvious photobleaching effect under irradiation within the time frame of the measurement. This photobleaching phenomenon is very frequently encountered in other metal complex-doped hybrid materials in which only weak physical interactions exist between the dopants and the matrix [22,34]. However, the other three Ru(II) covalently grafted samples are more stable because of the existence of strong Si-CH 2 bonds between the inorganic and the organic components.…”

Preparation, characterization, and luminescence properties of novel hybrid material containing europium(III) complex covalently bonded to MCM-41

“…During sample preparation, a large number of surface defects are involved in the inner surface of pores, acting as nonradiative relaxation paths. Under UV light exposure, the defects are modified gradually, causing photoluminescence increase [24,25].…”