Synthesis and characterization of Eu3+ activated hexagonal ABaGd(PO4)2 (A+=Li, Na, or K) phosphates

Abstract

E 3+ and ABaGd0.5(PO4)2 :En3.~ (where A+= Li, Na or K) double phosphates Abstract. BaGd0.s(PO4)2 : uo. 5 were synthesized by solid state diffusion method. These powders were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. XRD results showed many distinct lines in the XRD spectra. SEM measurement showed grains of different sizes in double phosphates. The Eu3+-ion emission lines for SD 0-> 7Fj (j = 1, 2, 3, and 4) transitions showed a splitting into 3, 2, 1, and 2 components, respectively. E 3+ double phosphate. Strength of these lines was enhanced by the addition of alkali ion to BaGdo.s(PO4)2 : Uo. 5 However, as the alkali ion varied from Li ÷ to K ÷, the intensity of 5/90-> 7F2 line (617 nm) in the red region increased at the cost of 5D 0-> 7F1 line (599 nm) in the orange region. Suitable explanation has been proposed for this phenomena.

Preparation and characterization of Eu3+ activated CaSiO3, (CaA)SiO3 [A = Ba or Sr] phosphors

“…5 0 3 Eu ⋅ + (where A = Li, Na, and K), emission lines for magnetic ( 5 D 0 → 7 F 1 ) and forced electric dipole transitions ( 5 D 0 → 7 F 2 ) were observed (Band et al 1999). These are consistent with the earlier reported results (Oomen and van Dongen 1989).…”

“…Particularly Sm and Eu ions are known to be stable in trivalent as well as in divalent states. Photoluminescence (PL) of europium has been extensively studied in different hosts (Ohnishi 1983;Welker 1991;Upadeo and Moharil 1996;Otvos and Peto 1998;Band et al 1999). Eu 3+ exhibits a red or orange luminescence, while Eu 2+ strongly depends on the host and it may emit anywhere from UV to deep red region.…”

“…Recently, we have published Eu 3+ activated CaWO 4 (Pode and Dhoble 1997) and A-BaGd (PO 4 ) 2 (A = Li, Na or K) (Band et al 1999) as red phosphors. Eu 2+ has been extensively used in obtaining the blue component of lamp phosphors (Smets 1987), colour TV (Welker 1991), Xray imaging phosphors (Wanmaker and ter Vrugt 1967;Meijerink and Blasse 1989;Crawford and Bixner 1991;Moharil 1994), in lamps for photocopying (Wanmaker and ter Vrugt 1967) etc.…”