Synthesis and luminescent properties of novel red-emitting M7Sn(PO4)6:Eu3+(M= Sr,Ba) phosphors
Novel Eu3+-activated M7Sn(PO4)6 (where M = Sr, Ba) red-emitting phosphors were synthesized via conventional solid-state reaction method at 1200 ?C for 2 h. The luminescence properties of the prepared samples and quenching concentration of Sr7-xSn(PO4)6 :xEu3+ and Ba7-xSn(PO4)6 :xEu3+ were investigated. These phosphors can be efficiently excited by UV (395 nm) and visible blue (465 nm) light nicely matching the output wavelengths of the near-UV LEDs and InGaN blue LED chips and emit the red light. The critical concentrations of the Eu3+ activator were found to be 0.175mol and 0.21mol per formula unit for Sr7-xSn(PO4)6 :xEu3+ and Ba7-xSn(PO4)6 :xEu3+, respectively. The M7-xSn(PO4)6 :xEu3+ (M = Sr, Ba) phosphor may be a good candidate for light-emitting diodes application.