Yellowish green-emitting KSrPO4:Tb3+ phosphors with various doping concentrations prepared by using microwave assisted sintering

KSr1−xPO4:xTb3+ phosphors with various concentrations (x = 0.05, 0.06, 0.07, 0.08) of Tb3+ ions were synthesized in succession by using microwave assisted sintering. The sintering condition was set at 1200 °C for 1 h in air. The microstructural and luminescent characteristics of KSrPO4:Tb3+ phosphors were investigated and are discussed here. The XRD result shows that the prepared KSr1−xPO4:xTb3+ phosphors would have an impure phase as the Tb3+ ion increases to more than x = 0.06. The photoluminescence measurement shows that the series of the emission-state 5D4 → 7F6, 5D4 → 7F4, and 5D4 → 7F3, corresponding to the typical 4f → 4f intra-configuration forbidden transitions of Tb3+, are appeared and the major emission peak is around at 542 nm. Moreover, the maximum photoluminescence intensity is appeared when the molar concentration of Tb3+ is 0.06. The decay time value of the KSr1−xPO4:xTb3+ phosphors with x = 0.06 is about 0.27 ms.