Cerium and terbium ions doped strontium aluminosilicate polycrystalline phosphors

Cerium and terbium ions doped strontium aluminosilicate polycrystalline phosphors with monoclinic structure identified to I2/c space group were synthesized by the high temperature solid-state reaction. Differential NUV-blue fluorescence behaviors of Ce³⁺ were exhibited under UVB radiation, which were originated from the luminescence centers with different crystal field environment. Bright green fluorescence of Tb³⁺ was released under UVA radiation, and with the intervention of Ce³⁺ ions, the effective excitation spectral range of Tb³⁺ ions was extended from UVA to UVB due to the energy transfer from Ce³⁺ to Tb³⁺. Upon the excitation in extended region, the luminescence intensity of Tb³⁺ was remarkably strengthened by a maximum fluorescence sensitization factor of ~152. These results demonstrate that Ce³⁺ and Tb³⁺ doped SrAl₂Si₂O₈ polycrystals are valuable NUV-blue and green phosphors, which have potential applications for phototherapy and color display.