A Study of Emission Color-Tuning in Yellow Long Persistent Phosphor (Sr_1-xCa_x)₃B₂O₆: Eu²⁺, Dy³⁺

A series of (Sr1-xCax)3B2O6: 0.001Eu2+, 0.005Dy3+ (x = 0–1) phosphors were synthesized by solid-state reaction. The crystal structure of Sr3B2O6 and Ca3B2O6 were both rhombohedral structures with space group Rc but different with lattice parameters. All the samples (except for x = 1) showed a wide characteristic emission band due to the Eu2+ transitions from 4f to 5d. The emission color in this study was tuned by controlling the concentration of Ca2+. And the Eu2+ emission band shifted to short-wavelength behavior with increasing Ca2+ was also explained. (Sr1-xCax)3B2O6: 0.001Eu2+, 0.005Dy3+ (x = 0.02, 0.05, 0.1, 0.2, 0.5, 0.8) samples with different afterglow times from 0.5 h to 1 h. Furthermore, the other necessary characteristics and possible mechanism were discussed and proposed.