Synthesis And Luminescent Performance Of Alkaline-earth Silicate Luminescent Materials Doped With Rare Earth Ions

In this paper,a series of novel luminescent materials have been synthesized,most of which are doped with rare earth ions.The introduction of rare earth ions into the silicate matrix changes the type of cations in the crystal lattice.XRD and fluorescence spectrophotometer were used to study the phases and photoluminescence properties of the materials.Several polychromatic luminescent silicate-based phosphors suitable for excitation by near-ultraviolet light sources have been studied.This article focuses on the following research work:1)A series of M2SiO4:Ce3+(M=Mg2+,Ca2+,Sr2+and Ba2+)phosphors were successfully prepared through high temperature solid phase reaction at 1400℃.Through X-ray diffraction(XRD)and photoluminescence spectroscopy(PL),their phase composition and luminescence properties were studied.According to the crystal field strength and the main crystal structure,the emission band of the doped Ce3+was discussed in detail,and the possible luminescence mechanism in the M2SiO4:Ce3+phosphor was proposed.2)A series of Mg2SiO4:Mn2+materials doped with different rare earth cations(La3+,Ce3+,Pr3+,Nd3+,Sm3+,Eu3+,Tb3+and Dy3+)were prepared by high-temperature solid-phase reaction and studied to improve their luminous properties.The effect of rare earth cations on its luminescence performance was revealed in detail,and a possible mechanism for enhancing its luminescence was established.The effect of 4f orbital on Mg2SiO4:Mn2+materials was revealed,and the sensitization effect of rare earth ions on the luminescence center of red fluorescent materials was discussed.3)M2SiO4:Tb3+,Mn2+,Nd3+(M=Mg2+,Ca2+,Sr2+,and Ba2+)phosphors suitable for near-ultraviolet-violet radiation excitation were successfully prepared at 1400℃ in N2 atmosphere by a high-temperature solid-state reaction,and their phase compositions and luminescent performance were also studied by X-ray diffraction(XRD)and photoluminescence spectra.Results show that their emission intensity increases in the order of Ca2SiO4>Mg2SiO4>Sr2SiO4>Ba2SiO4 matrix phosphor.Ca1.94SiO4:0.02Tb3+,0.02Mn2+,0.02Nd3+ phosphor exhibits the best luminescence performance.