Eu3+ 이온이 첨가된 세슘 몰리브덴산염 형광체의 분광학 특성

Abstract

Luminescence properties of red-light-emitting Cs2Mo5O16:Eu3+ phosphors are investigated by the laser-excitation spectroscopy at room temperature. The phosphors were synthesized by solid state reaction and the formation of the samples was characterized by X-ray powder diffraction analysis. The patterns are in the good agreement with standard (ICSD 83754). The optimum temperature to synthesize the Cs2Mo5O16:Eu3+ phosphors are estimated to be 450 oC by thermogravimetry and differential thermal analysis. The excitation and emission spectra of Cs2Mo5O16:Eu3+ (0, 0.01, 0.1, 1, 5, 10 mol %) are measured by optical spectrometer equipped with Xe lamp. The strong excitation lines in the wavelength region 350-470 nm are attributed to the 7F0 → 5L6 transition and the 7F0 → 5D2 transition of Eu3+ in Cs2Mo5Mo16. The strong excitation bands due to the ligand to metal ion charge transfer (CT) transition of Cs2 and O2- - Eu3+ CT transition are observed in the UV region for Eu3+ -doped Cs2Mo5O16 phosphors. Emission spectrum shows the strong lines at 550-680 nm corresponding to the 5D0 → 7F1 and 5D0 → 7F2 transitions. The maximum luminescence intensity is obtained at Eu3+ concentration of 10 mol%. The difference in luminescence properties by changing the doping concentration of Eu3+ are discussed in relation with crystal structure of Cs2Mo5O16.