The defect aggregation of RE3+ (RE = Y, La ∼ Lu) in MF2 (M = Ca, Sr, Ba) fluorites

Site Occupancies, VUV-UV–vis Photoluminescence, and X-ray Radioluminescence of Eu2+-Doped RbBaPO4

“…Eu 2+ is one of the lanthanide ions and has 4f 7 electronic configuration. It shows 5d-4f emission when the lowest 4f 6 5d state is located below the 6 PJ level, and has been extensively studied for applications in lighting, display and scintillation detection. BaMgAl10O17: Eu 2+ has been a suitable blue-emitting phosphor in tricolor lamps for years, BaFCl:Eu 2+ is the first commercially available rare-earth X-ray phosphor, SrAl2O4: Eu 2+ , Dy 3+ is a long phosphorescent phosphor with high brightness and is widely applied, SrI2: Eu 2+ is a scintillator with high light output for detecting ionizing radiation, and Sr[LiAl3N4]: Eu 2+ is considered to be a potential red-emitting phosphor for next-generation high-power phosphor-converted white-light-emitting diodes.…”

“…The following aspects are essential for the development of novel Eu 2+ -doped luminescent materials. First, the site occupancy of the doping lanthanide ion must be clarified, because it is one of the most crucial factors for the excitation and emission wavelengths of Eu 2+ in a specific host compound. , For instance, the excitation peaks of Eu 2+ in the 10-fold coordinated Sr 2+ site and 6-fold coordinated Ca 2+ site of Li 4 SrCa­(SiO 4 ) 2 are found at ∼290 and ∼375 nm, respectively . The emission bands at ∼472, ∼445 and ∼406 nm are assigned to Eu 2+ at Sr­(I)­O 9 , Sr­(III)­O 8 , and Sr­(II)­O 7 polyhedral sites in Sr 5 SiO 4 Cl 6 , respectively .…”

Modelling and analyzing the glass-like heat transfer behavior of rare-earth doped alkaline earth fluoride crystals

“…The huge divergence of the microstructure (cluster) results in the variation of the lattice distortion and system disorder degree, thus generating differentiated thermal conductivities in different fluoride systems. 22,36,[41][42][43][44][45][46] As shown in Fig. 11, with the increase of the atomic number, and Yb:CaF 2 with doping concentration higher than 1 at%.…”

“…To precisely delineate such an attractive phenomenon, some explorative research has been carried out by our group previously. 38,41 It has been inferred that the differentiated heat transfer performance at relatively high doping concentrations is mainly induced by the diversity of clusters generated from different RE doped ions. As shown in Fig.…”

Mid-IR Optical Property of Dy:CaF2-SrF2 Crystal Fabricated by Multicrucible Temperature Gradient Technology

“…CaF 2 -SrF 2 crystal was selected as host material with a molar ratio of 1:1 for Ca/Sr, as inspired by predominant optical properties when doped with rare-earth ions such as Yb 3+ [19,20]. Meanwhile, CaF 2 -SrF 2 possesses low phonon energy, which is of benefit to weaken nonradiative decay from intermediate states to lower ground states in rare-earth ions [21,22]. Moreover, CaF 2 -SrF 2 is an azeotrope system, and even the composition ratio of Ca/Sr is different [23,24].…”