| Traditional aluminate persistent phosphors have the superior luminescence performance, but due to theirs poor stability, the silicate persistent phosphors get more and more attentions, Because of the physical and chemical stability, resistance to water moisture resistance and other advantages. The RE3+ electronegativity is the ability of attracting carriers. Throughing changing the attracting carriers ability by the RE3+ electronegativity, in order to control the luminescence performance; There were few reports showing how to choose auxiliary activator, choosing Bi3+ as the auxiliary activator because of its suitable electronegativity and ionic radius,; Finally the ion doping concentration was playing an important role of effect on the luminescence performance.Persistent phosphors of Ba5Si8O21:Eu2+, RE3+ were successfully synthesized by the solid state reaction. The persistent phosphors of Ba5Si8O21:Eu2+, RE3+(RE=Nd, Dy, Ho) exhibit excellent phosphorescence. After activation, Ba5Si8O21:Eu2+, Nd3+ emits with persistent luminescence beyond 8 h. The weakest La3+ electronegativity results in the inferior persistent luminescence property even though the sample emits the intensest PL emission. Codoping Bi3+ as the auxiliary activator because of its suitable electronegativity and ionic radius, the afterglow intensity and thermoluminescence intensity increased. Codoping Bi3+ could enhance Ba5Si8O21: Eu2+ persistent phosphors performance. With Codoped different concentrations of Ho3+ or Bi3+ as auxiliary activator, itwas found that the codoped Ho3+ sample photoluminescence intensity reached the highest value when x=0.09 and the codoped Bi3+sample persistent luminescence properties reached the best value when x=0.02. With the increasing of doping concentration, the samples got concentration quenching and the luminescence properties decreased.
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