| A highly efficient white phosphor, CaxSr1-x(NbO3)2:Pr3+(0≤x≤1) and Ca(NbO3)2:Pr3+,Bi3+, have been synthesized using a traditional high-temperature solid method and we researched the influence of optical properties by doping alkali metals and halide in the phosphor system CaxSr1-x(NbO3)2:Pr3+(0≤x≤1). Meanwhile, the structures, morphologies and optical properties of products prepared were characterized by using XRD, FESEM and PL, respectively. Besides, we also investigated the doping concentration and calcination temperature had effect on the luminous intensity of the samples prepared, at the same time, the luminescent mechanism of materials prepared was discussed preliminary.CaxSr1-x(NbO3)2:Pr3+(0≤x≤1) white phosphors were fabricated successfully by high-temperature solid method via annealing at different temperature. The sizes of particles prepared are 0.4-1μm and a strong blue emission band centered at 460 nm is observed under 200-350 nm excitation. The emission band of the samples is at 350-700 nm in the visible range under 200-350 nm UV-light excitation, of which the best Pr3+ ion concentration is 0.005 and the best Ca2+ ion concentration is 0.8, the best calcination temperature is 1200℃.Alkali metal and halide were introduced to the phosphor system CaxSr1-x(NbO3)2:Pr3+(0≤x≤1) and the alkali metal and halide co-doped phosphors prepared were synthesized by adding appropriate amounts of alkali halide into the mixtures of CaCO3,SrCO3,Nb2O5,Pr6O11. It can play an important role in balancing the charge for doping alkali metal and halide into the materials prepared. The luminous intensity of the samples prepared was enhanced significantly by doping alkali metal and halide in the phosphor system CaxSr1-x(NbO3)2:Pr3+(0≤x≤1). Then the concentration of alkali metal and halide produced an effect on the luminous intensity of the materials prepared was researched.In our paper, we synthesized the Ca (NbO3)2:Pr3+, Bi3+ materials with calcium niobate as the substrate. It can be observed that the emission bond of the phosphors prepared broaden at 300-700 nm under 254 nm from the fluorescence spectrum of the materials analyzed. The emission band of the materials was consisted of the emission peaks of calcium niobate and luminescence centers Bi3+ and Pr3+ which generated by electronic orbital transition of bismuth ion and praseodymium ion. The luminescence intensity of Ca(NbO3)2:Pr3+,Bi3+ materials is high at low voltage, the cost of the raw materials is low, the material method is simple and can be doped easily. So, the materials have the potential applied in the phosphor for lamp.
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