Effect of H₃BO₃ on the phase stability and long persistence properties of Sr_3.96Al₁₄O₂₅:Eu_0.012+, Dy_0.023+ phosphor

Sr_3.96Al₁₄O₂₅:Eu²⁺,Dy³⁺ long persistent materials with different weight of H₃BO₃ prepared by the high temperature solid-state reaction method were characterized by X-ray powder diffraction (XRD), scanning electronic microscope (SEM), photoluminescence spectra (PL), and thermoluminescence (TL). The results of XRD indicate that the 3% addition of H₃BO₃ is in favor of the formation of pure phase Sr₄Al₁₄O₂₅, and SrAl₁₂O₁₉ was generated when H₃BO₃ is in low content or high content. The average grain sizes of samples grow bigger during the increasing of H₃BO₃. PL spectra show that the emission peak does not shift evidently and the emission intensity changes a little, indicate that the different amount of H₃BO₃ have a little inference to the crystal field. The decay characteristics and TL measurement show that H₃BO₃ affect the afterglow properties of Sr_3.96Al₁₄O₂₅:Eu²⁺,Dy³⁺, because the increasing of H₃BO₃ lead to more defects in Sr₄Al₁₄O₂₅ matrix.