Study of the ionic conductivity of Ca6La4(PO4)2(SiO4)4F2 and Ca4La6(SiO4)6F2

Structure and luminescence properties of La6Ba4(SiO4)6F2:Dy3+ phosphor with apatite structure

“…21,22 Apatite-type compounds crystallize in the space group of P6 3 /m (Z ¼ 2) and have a general chemical composition of A 10 [XO 4 ] 6 Z 2 , 23 where A stands for divalent cations such as Ca 2+ , Mg 2+ , Ba 2+ and Sr 2+ ; XO 4 represents a tetrahedron group in which X can be P, Si, Ge, V; Z can be anions such as OH À , Cl À , O 2À , F À . [24][25][26] By isomorphic substitution, the A site can be occupied by rare earth ions like Y 3+ , La 3+ , Gd 3+ or alkali metal ions like Li + , Na + , K + . [27][28][29] Accordingly, we can skillfully design novel Dy 3+ -doped phosphors with more accomplished light output for solid state lighting applications.…”

High Thermal Stability Apatite Phosphors Ca2La8(SiO4)6O2:Dy3+/Sm3+ for White Light Emission: Synthesis, Structure, Luminescence Properties and Energy Transfer

“…As observed, there are similar XRD patterns for the CLSO host and doped samples. And no impurity phase peaks appear, which indicates that rare earth ions substitute the host lattice causing little changes in crystal structure, due to ion radii of Dy 3+ (r = 0.97 Å for CN = 7 and r = 1.08 Å for CN = 9)and Sm 3+ (r = 1.02 Å for CN = 7 and r = 1.13 Å for CN = 9)are close to that of La 3+ (r = 1.10 Å for CN = 7 and r = 1.22 Å for CN = 9)of the CLSO host 12,19,20 . JADE6.5 software was utilized to analyze these XRD patterns, based on Scherrer’s equation and lattice strain theory, and analysis results, shown on Table 1, demonstrate all samples belonging to hexagonal apatite structure and space group P6 3 /m.…”

Synthèse et caractérisation de strontium–calcium–lanthane apatites Sr7−xCaxLa3(PO4)3(SiO4)3F2 0 ≤ x ≤ 2

“…De la me ˆme manie `re, il est possible d'attribuer le changement de pente dans le cas pre ´sent a `la liaison Sr/La-F. En effet, comme il a e ´te ´indique ´plus haut, la courbe d'Arrhenius de la fluorapatite calcique ou strontique est constitue ´e d'une seule droite [2]. Il en est de me ˆme pour les apatites, alors que celle du compose ´Ca 6 La 4 (PO 4 ) 2 (SiO 4 ) 4 F 2 [46] est forme ´e de deux branches. En revanche, la courbe de Ca 6 La 4 (PO 4 ) 2 (-SiO 4 ) 4 O [47] ne comporte pas de cassure, bien que le lanthane soit aussi pre ´sent.…”