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CaSiO_3∶Eu~ 3+ _ 0.08 Bi~ 3+ _ 0.002 with a monoclinic perovskite structure was synthesized by using sol-gel method, and its luminescence characteristics were investigated. From the excitation spectrum, it can be seen that the main peaks located at 238, 396, 415, 437 and 359 nm correspond to the charge-transfer band of Eu~ 3+ —O~ 2- , the absorption transitions of ~7F_ 0,1 → ~ 5 L_6, ~7F_ 0 → ~ 5 D_3, ~7F_1→ ~ 5 D_ 3 of Eu~ 3+ ions, and ~ 3 P_1→ ~ 1 S_ 0 of Bi~ 3+ ions, respectively. When the samples were excited with a light of wavelength 359 or 395 nm, it can be seen from the emission spectrum that the electronic dipole transition located at 609 nm corresponding to ~ 5 D_ 0 → ~ 7 F_2 of Eu~ 3+ ions was stronger than the magnetic dipole transition located at 587 nm corresponding to ~ 5 D_ 0 → ~ 7 F_ 1 of Eu~ 3+ ions, which shows that more Eu~ 3+ ions were located in nonreversion center lattices. The energy transfer from Bi~ 3+ ions to Eu~ 3+ ions in the phosphor was also discussed. The results show that Eu~ 3+ ions could be well sensitized by Bi~ 3+ ions, and the energy-transfer pattern between Bi~ 3+ ions and Eu~ 3+ ions was resonance energy transfer.
From the excitation spectrum, it can be seen that the main peaks located at 238, 396, 415, 437 and 359 nm correspond to the charge-transfer band of Eu ~ 3+ -O ~ 2-, the absorption transitions of ~7F_0,1 → ~5 L_6, ~7F_0 → ~5 D_3, ~ 7F_1 → ~ 5 D_3 of Eu ~ 3+ ions, and ~ 3 P_1 → ~ 1 S_0 of Bi ~ 3+ ions, respectively. When the samples were excited with a light of wavelength 359 or 395 nm, it can be seen from the emission spectrum that the electronic dipole transition located at 609 nm corresponding to ~ 5 D 0 → ~ 7 F 2 of Eu ~ 3 ions were stronger than the magnetic dipole transition located at 587 nm corresponding to ~ 5 D 0 → ~ 7 F_ 1 of Eu ~ 3+ ions, which shows that more Eu ~ 3+ ions were located in nonreversion center lattices. The energy transfer from Bi ~ 3+ ions to Eu ~ 3+ ions in the phosphor was al so discussed. The results show that Eu ~ 3 + ions could be well sensitized by Bi ~ 3+ ions, and the energy-transfer pattern between Bi ~ 3+ ions and Eu ~ 3+ ions was resonance energy transfer.