Substitution of oxygen by fluorine in the GdSr_2AlO_5:Ce^3+ phosphors: Gd_1−xSr_2+xAlO_5−xF_x solid solutions for solid state white lighting

Abstract

Solid solutions between two isotypic host compounds: GdSr(2)AlO(5) and Sr(3)AlO(4)F; Gd(1-x)Sr(2+x)AlO(5-x)F(x):Ce(3+) (GSAF:Ce(3+)), have been prepared across the complete solid solution range x. Depending on x, the series display considerable optical tunability of emission wavelengths in the range 574 nm to 474 nm, which is attributed to the decreased crystal field splitting arising from increased host ionicity with fluorine addition. Applying the GSAF:Ce(3+) phosphors on InGaN LEDs (lambda (max) = 405 nm and 450 nm) permits white lighting sources to be prepared. The characteristics of these are reported.

Recent progress in luminescence tuning of Ce3+and Eu2+-activated phosphors for pc-WLEDs

“…[136][137][138] The replacement of Al 3+ by Si 4+ and of F À by O 2À not only compensate charge, but also more importantly change the local environment of the lattice. According to this strategy, Seshadri' group have made much effort to modify and develop newly oxyfluoride-based pc-WLED phosphors recently.…”

Efficient and Color‐Tunable Oxyfluoride Solid Solution Phosphors for Solid‐State White Lighting

“…We previously reported a solid solution between the phosphor host compound, LaSr 2 AlO 5 37 and SSO,38 as well as phosphor hosts from the solid solution of GdSr 2 AlO 5 and SAF 39. For SASF:Ce 3+ , two substitutions occur across the solid solution series, both of anions (O 2− for F − ) and of cations (Si 4+ for Al 3+ ), which impart superior phosphor properties.…”

A single-phase full-color phosphor based on Ba 3 MgSi 2 O 8 co-activated with Eu 2+ , Tb 3+ , and Mn 2+

“…Earlier reports of tri-band (i.e., blue, green and red) luminescence [12,16,17] from Eu 2þ and Mn 2þ co-activated samples have significant amounts of orthosilicate (Ba 2 SiO 4 ) impurities, which exhibit a broad and very efficient emission band centered around 505 nm [18,19]. However, a true full-color emitting phosphor based on Ba 3 MgSi 2 O 8 has not yet been reported.…”