Abstract: A green phosphor, KBaPO₄:Tb³⁺, was synthesized by the high temperature solid-state method, using Li₂CO₃, Na₂CO₃, K₂CO₃, BaCO₃, NH₄H₂PO₄, NH₄Cl, Tb₄O₇ and CeO₂ as starting materials. After these individual materials were blended and grounded thoroughly in an agate mortar, the homogeneous mixture was heat-treated at 950℃ for 3 h, and the phosphors were obtained. The samples was characterized by powder X-ray diffraction (XRD) (D/max-rA, Cu Ka, 40 kV, 40 mA, λ=0.15406 nm). The spectral characteristics of these phosphors were measured by a SHIMADZU RF-540 fluorescence spectrophotometer. KBaPO4:Tb3+ phosphor shows several emission peaks located at 437, 490, 545, 586 and 622 nm which correspond to the ⁵D₃→⁷F₄ and ⁵D₄→⁷F_J=6. 5, 4, 3 transition of Tb³⁺, respectively, and the highest emission peak is 545 nm. Monitored at 545 nm emission, the excitation spectrum consists of several bands, and the highest peak locates at 380 nm. The effects of Tb³⁺ doping content, the compensators (Li⁺, Na⁺, K⁺ or Cl^-), and the sensitize activator Ce³⁺ on the emission intensity of KBaPO₄: Tb³⁺ phosphor are studied. The results show that the emission intensity can be controlled by the above factors, and the intensity can be enhanced by the selection of the optimal condition. It indicates that KBaPO₄:Tb³⁺ is a promising green phosphor for white light emitting diodes.

Key words: white LED, KBaPO₄,Tb³⁺, luminescent characteristics