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The persistent luminescence of CdSiO 3 :Tb 3+ was investigated with photoluminescence, thermoluminescence (TL), synchrotron radiation X-ray absorption (XANES and EXAFS) and UV-VUV spectroscopies. Only the typical intraconfigurational 4f 8 −4f 8 transitions of the Tb 3+ ion were observed with no traces of band emission in either the conventional UV excited or persistent luminescence spectra. The trap structure from TL with three traps from 0.65 to 0.85 eV is ideal for room-temperature persistent luminescence similar to, e.g., Sr 2 MgSi 2 O 7 :Eu 2+ ,R 3+ . Despite the rather low band gap energy, 5.28 eV, the persistent luminescence from Tb 3+ is produced only under UV irradiation due to the inauspicious position of the 7 F 6 ground level deep in the band gap of CdSiO 3 . This confirms the role of electrons as the charge carriers in the mechanism of Tb 3+ persistent luminescence. The XANES spectra indicated the presence of only the trivalent Tb 3+ species, thus excluding the direct Tb 3+ → Tb IV oxidation during the charging process of persistent luminescence. Eventually, a unique persistent luminescence mechanism for Tb 3+ in CdSiO 3 was constructed based on the comprehensive experimental data.

The design of bifunctional magnetic luminescent nanomaterials containing Fe3O4 functionalized with rare earth ion complexes of calixarene and β-diketonate ligands is reported. Their preparation is accessible through a facile one-pot method. These novel Fe3O4@calix-Eu(TTA) (TTA = thenoyltrifluoroacetonate) and Fe3O4@calix-Tb(ACAC) (ACAC = acetylacetonate) magnetic luminescent nanomaterials show interesting superparamagnetic and photonic properties. The magnetic properties (M-H and ZFC/FC measurements) at temperatures of 5 and 300 K were explored to investigate the extent of coating and the crystallinity effect on the saturation magnetization values and blocking temperatures. Even though magnetite is a strong luminescence quencher, the coating of the Fe3O4 nanoparticles with synthetically functionalized rare earth complexes has overcome this difficulty. The intramolecular energy transfer from the T1 excited triplet states of TTA and ACAC ligands to the emitting levels of Eu(3+) and Tb(3+) in the nanomaterials and emission efficiencies are presented and discussed, as well as the structural conclusions from the values of the 4f-4f intensity parameters in the case of the Eu(3+) ion. These novel nanomaterials may act as the emitting layer for the red and green light for magnetic light-converting molecular devices (MLCMDs).