Tuning Eu²⁺ luminescence in Sr₈CaLu (PO₄)₇via Na⁺-induced local structure engineering for violet-chip-excitable full-spectrum lighting

Abstract

We develop a new type of violet-light-excitable Eu2+:Sr8CaLu(PO4)7 phosphor with tunable green–yellow emissions and high photoluminescence quantum yields above 70% via Na+ alloying-induced local structural modification.

Preparation of a novel violet-excitable Na3YSi2O7:Eu2+ green phosphor via salt-flux assistance and its luminescence properties

“…The rare earth ion Eu 2+ is a good activator ion because it has a unique crystal field-sensitive electronic structure that enables it to have abundant emission in different matrix materials. Some Eu 2+ activated luminescent materials have been reported, such as Sr 3 TaO 5.5 :Eu 2+ , 14 (Ba, Sr) 2 LaGaO 5 :Eu 2+ , 15 NaLi 3 SiO 4 :Eu 2+ , 16 SrLaScO 4 :Eu 2+ , 17 Ba 5 Si 11 Al 7 N 25 :Eu 2+ , 18 (Sr, Ba) 3 Li 4 Si 2 N 6 :Eu 2+ , 19 Na 3 K 5 (Li 3 SiO 4 ) 8 :Eu 2+ , 20 BaAl 4 Sb 2 O 12 :Eu 2+ , 21 Sr 8 CaLu(PO 4 ) 7 :Eu 2+ , 22 CaLuGaO 4 :Eu 2+ , 23 Sr 9 Ca(Li, Na, K)(PO 4 ) 7 :Eu 2+ 24 and Sr 5 Si 2 P 6 N 16 . 25 The A 3 BSi 2 O 7 (A = Na, Rb, K; B = rare-earth metal ions) matrix materials have a rich spatial structure, which can provide a rich crystal field environment for active ions.…”