New NaSrPO4:Sm3+ phosphor as orange-red emitting material

Sm3+-activated NaSrPO4 phosphors could be efficiently excited at 403 nm, and exhibited a bright red emission mainly including four wavelength peaks of 565, 600, 646 and 710 nm. The highest emission intensity was found for NaSr (1-x) PO4: xSm(3+) with a composition of x = 0.007. Concentration quenching was observed as the composition of x exceeds 0.007. The decay time values of NaSr1-x PO (4) : xSm(3+) phosphors range from around 2.55 to 3.49 ms. NaSr1-x PO4: xSm(3+) phosphor shows a higher thermally stable luminescence and its thermal quenching temperature T (50) was found to be 350A degrees C, which is higher than that of commercial YAG:Ce3+ phosphor and ZnS:(Al, Ag) phosphor. Because NaSr1-x PO4: xSm(3+) phosphor features a high colour-rendering index and chemical stability, it is potentially useful as a new scintillation material for white light-emitting diodes.