The influence of processing parameters on photoluminescent properties of Ba 2ZnS 3:Ce phosphors by double-crucible method

Abstract

Green to yellowish green light emitting of Ce 3+-doped barium zinc sulfide (Ba 2ZnS 3) phosphor powders have been synthesized by a double-crucible method. XRD results indicate that the raw materials are completely sulfurized above 950 °C, and possess orthorhombic crystal structure with increasing doping concentration from 0 to 1 mol%. The photoluminescence (PL) spectra show that the emission peaks located in the 502–532 nm range (under excitation at λ ex=422 nm) and in the 530–560-nm range (under excitation at λ ex=358 nm) depend on the doping concentration of the Ce 3+ ions. The emission spectra resulted from the 2D(5d)– 7F 5/2(4f) and 2D(5d)– 7F 7/2(4f) Ce 3+ transitions. The Ba 2ZnS 3 doped with 0.5 mol% Ce 3+ and prepared at 950 °C for 16 h has the highest luminescent intensity; the emission wavelength λ em is around 530 nm (at λ ex=422 nm) and the CIE coordinate is x=0.33, y=0.53.