Abstract:

In order to enhance the luminous intensity and color purity of red phosphor,using calcium nitrate,sodium nitrate,europium nitrate,ammonium dihydrogen phosphate,ammonium molybdate and barium nitrate as raw materials,a series of red phosphors of NaCa_1-xPO₄：xEu³⁺、NaCa_1-x（PO₄）_1-y（MoO₄）_y：xEu³⁺、NaCa_1-x-zPO₄：xEu³⁺,zBa²⁺ were synthesized by high temperature solid phase method.The effect of mono-doping Eu³⁺ and co-doping Eu³⁺/MoO₄^2- and Eu³⁺/Ba²⁺ phosphors on the luminescent properties of the phosphors were investigated.The structure of the phosphors was characterized by X-ray diffraction（XRD）,fluorescence spectrophotometer and color coordinates.The results showed that the crystal system of NaCaPO₄ did not change after doping Eu³⁺,MoO₄^2- and Ba²⁺,but the crystal cell parameters changed,indicating that Eu³⁺,MoO₄^2- and Ba²⁺ entered the lattice of NaCaPO₄.Under the excitation of ultraviolet light at 393 nm,the emission spectra of phosphors showed two characteristic emission peaks of Eu³⁺,which belonged to the transition of⁵D₀→⁷F₁ and⁵D₀→⁷F₂ of Eu³⁺.Compared with the mono-do-ped Eu³⁺ phosphor of 16%,in the emission spectra of the co-doped 16%Eu³⁺/3%MoO₄^2- or 16%Eu³⁺/6%Ba²⁺ phosphor,the emission peak intensity generated by⁵D₀→⁷F₂ transition was higher than that of the mono-doped Eu³⁺ phosphor of 16%.The emission intensity ratios（R） of⁵D₀→⁷F₂ and⁵D₀→⁷F₁ were 1.76（R_Mo） and 1.28（R_Ba）,respectively,which were higher than that of mono-doped R_Eu（0.99）.The color purity of co-doped Eu³⁺/MoO₄^2- phosphor was better than that of mono-doped Eu³⁺ and co-doped Eu³⁺/Ba²⁺ phosphors.

Key words: red phosphor, luminescence performance, near UV excition