title: [Effect of Eu3+ molar ratio on the spectra of Y2O2:Eu3+, Mg2+ and Ti4+ red phosphor].
abstract: Synthesis of Y2O2S:Eu3+, Mg2+ and Ti4+ red phosphor by flux fusion method was presented. The decay curve of Y2O2S:Eu3+, Mg2+ and Ti4+ red phosphor was measured and the afterglow time was over one hour. The emission spectra and excitation spectra were measured, and the effect of Eu3+ molar ratio on the emission spectra and excitation spectra were also discussed. The emission spectra showed that Y2O2S:Eu3+, Mg2+ and Ti4+ had narrow emission peaks. The emission peaks ascribed to Eu3+ ions transition from 5D(J) (J = 0, 1, 2, 3,) to 7F(J) (J = 0, 1, 2, 3, 4, 5) were found. With the increase of Eu3+ molar ratio, the emission peaks 513.6, 540.1, 556.4, 587.3 and 589.3 nm ascribed to the energy transition 5D2, 5D1 to 7F(J) (J = 0, 1, 2, 3, 4) deteriorated gradually relative to the main emission peak at 627.0 nm. The emission peaks ascribed to energy transition 5D0 to 7F(J) (J = 0, 1, 2, 3, 4) didn't weaken relative to the main emission peak. It was probably due to the so-called true activator saturation effect. This function on the higher activated states 5D2 and 5D1 was more distinct. The excitation spectra of Y2O2S:Eu3+, Mg2+ and Ti4+ showed that it had excitation peaks at 350 nm nearby, which was ascribed to the absorption of charge transfer (Eu3+-O2-, Eu3+-S2-). The excitation peaks at 468, 520 and 540 nm were ascribed to the representative energy transition 4f-4f of Eu3+ ions. With the increase of Eu3+ molar ratio, the excitation peaks 468, 520 and 540 nm strengthened relative to the main absorption peak at 350 nm nearby.
authors.affiliation: Physics Science and Technology College, Hebei University, Baoding 071002, China.
authors.forename: Zhi-ping
authors.initials: ZP
authors.lastname: Yang
authors.forename: Zhi
authors.initials: Z
authors.lastname: Guo
authors.forename: Sheng-chao
authors.initials: SC
authors.lastname: Zhu
authors.forename: Wen-jie
authors.initials: WJ
authors.lastname: Wang