Luminescence behavior of Eu3+ in CaSiO3:Eu3+(Bi3+) and Sr2SiO4:Eu3+(Bi3+)

CaSiO3:Eu0.083+Bi0.0023+ and Sr2SiO4:Eu0.083+Bi0.0023+ were synthesized by the sol–gel method, and their structure and luminescence characteristics were investigated. The XRD results showed that the symmetry of Sr2SiO4:Eu0.083+Bi0.0023+ structure, which is similar to the non-close-packing orthogonal structure of K2SiO4 is higher than that of CaSiO3:Eu0.083+Bi0.0023+ perovskite structure belonging to the monoclinic system. From the excitation spectra of CaSiO3:Eu0.083+Bi0.0023+and Sr2SiO4:Eu0.083+Bi0.0023+, it can be seen that the main peaks located at 267 nm, 383 nm, 395 nm, 437 nm, 457 nm and 359 nm, which correspond to the charge transfer band of Eu3+–O2−, absorption transition of 7F0.1–5GJ, 7F0.1–5L6, 7F1–5D3 and 7F0.1–5D2 of Eu3+ ions and 3P1–1S0 of Bi3+ ions, respectively. When the CaSiO3:Eu0.083+Bi0.0023+ samples were excited with wavelength of 359 nm, the emission intensity of electronic dipole transition at 609 nm originated from 5D0–7F2 of Eu3+ ions was stronger than magnetic dipole transition at 587 nm originated from 5D0–7F1 of Eu3+ ions mainly due to the lower symmetry and the distortion of the structure. However, the opposite situation appeared in the emission spectrum of Sr2SiO4:Eu0.083+Bi0.0023+. In addition, the intensity comparison of each emission peaks between the emission spectra of CaSiO3:Eu0.083+Bi0.0023+ and Sr2SiO4:Eu0.083+Bi0.0023+ showed that the energy transfer efficiency between Bi3+ ions and Eu3+ ions in Sr2SiO4:Eu0.083+Bi0.0023+ is apparently higher than that in CaSiO3:Eu0.083+Bi0.0023+.