Preparation And Reseach Of Rare Earth Doped Yttrium Oxysulfide Red Long-lasting Material

Long-lasting phosphor in which energy could be reserved under the(ultraviolet) UV lamp or infrared femtosecond laser and finally thermal release as luminescence. Recently,long lasting phosphor has been rapidly developed.The phosphors available include blue,green,and red etc.Much work has been done on them.The studies focused mainly on rare earth doped phosphors,particularly alkaline earth aluminate system.The best known green afterglow material is SrAlO₄;Eu²⁺,Dy³⁺,blue afterglow material is CaAlO₄;Eu²⁺,Nd³⁺,both have been commercialized.However, the progress in developing red afterglow material is slow.Y₂O₂S;Eu³⁺was found as highly effective television powder without long lasting properties.In 2000 Yoshinori et al reported that Ti⁴⁺and Mg²⁺co-doped Y₂O₂S;Eu³⁺phosphor has high luminance red afterglow.In the first part of this paper,we reviewed the research advance and luminescent model of long-lasting phosphor,research status of red persistence phosphor and preparation methods of sulfide-oxide long-lasting phosphor; In the second part,the experiment method,raw material,main instrument and characterization methods et al were introduced; and in the third and the fourth parts,taking Y₂O₂S as matrix,we synthesized Y₂O₂S;Eu³⁺,Si⁴⁺,Zn²⁺and Y₂O₂S;Eu³⁺,Si⁴⁺,M²⁺(M=Mg,Ca,Sr,Ba) novel red long-lasting phosphors by solid state reaction.The effect of the content of Eu³⁺and preparation technology et al were studied.XRD and photoluminescence(PL) spectra as well as the luminance decay were used to characterize these long lasting phosphors.According to the thermo-luminescence spectra,we analysised the kinds of trap and calculated the trap deep.Then the best synthesis conditions were decided. And the effect of the doping of alkaline-earth metal ions in the phosphors Y₂O₂S;Eu³⁺, Si⁴⁺,M²⁺(M=Mg,Ca,Sr,Ba)was also analysised.