New insight in the structure–luminescence relationships of Ca9Eu(PO4)7

The luminescence spectroscopy and thermal stability of red-emitting phosphor Ca9Eu(VO4)7

“…5 D 0 transitions in Fig. 6 is agreed with this conclusion, and the three site positions of Eu 3+ ions are in good agreement with the results recently reported by Benhamou et al [25] They confirmed similar three site-distributions of Eu 3+ in Ca 9 Eu(PO 4 ) 7 at 578.5, 579.5, 580.1 nm for the M3, M1 and M2 sites, respectively, by means of X-ray diffraction and low temperature Eu 3+ luminescence studies [25]. Following this conclusion, it could be suggested that in Ca 9 Eu(VO 4 ) 7 , there are three cation positions occupied by Eu 3+ : M3 (578.65 nm), M1 (579.7 nm) and M2 (580.1 nm) as shown in Fig.…”

“…For example, the strong quenching of luminescence were observed in EuNa 2 Mg 2 (VO 4 ) 3 , EuK 5 (MoO 4 ) 4 and EuA(MoO 4 ) 2 (A = Na, K and Rb) [13]. The knowledge of the site-distribution over the different sites in a host structure will be useful to deeply analyze the luminescence mechanisms [25].…”

Persistent luminescence of Eu, Mn, Dy doped calcium phosphates for in-vivo optical imaging

“…If the doping ratio of small elements increases, they will gradually occupy Ca(1) and Ca(2) sites that share an oxygen atom with Ca(5). For bigger ions, such as Pr 3 þ and Eu 2 þ , Ca(1), Ca(2) and Ca(3) will be preferentially occupied [30,35]. Notice that distance Mn-O in β-TCP has been reported to be 2.26 Å [35].…”

The revised phase diagram of the Ca3(PO4)2–YPO4 system. The temperature and concentration range of solid-solution phase fields

“…The maximal doping of the a solid solution with RE amounts to *3 mass%. This may not be sufficient active ion content in the a phase necessary to achieve a long-lasting phosphorescence or to apply the material in thermoluminescence dosimetry [47].…”