Preparation And Characterization Of Luminous Glasses Based On Persistent Luminescent Strontium Aluminates

Persistent luminescence materials,as a kind of functional material,have been deployed in many fields like monitor,fiber amplifier,energy storage,etc.However,to become commercially viable,persistent luminescence materials have to overcome the barrier of its high cost and poor stability caused by water vapor.In order to solve those problems effectively,persistent luminescence materials are involved with glass acting as substrate called luminous glass,which with the properties of chemical,optical and mechanical.In the experimental process,luminous glass was prepared by borosilicate glass powder and strontium aluminate powder at high temperature.As well as the luminous glass exhibited high performance both phosphorescence and stability.The two-step method was adopted in the preparation.Firstly,the glass powder were crushed into 40 um after obtained by rapid cooling,then were melting into glass again,the glass powder mixed uniformly with the commercial persistent luminescence strontium aluminate luminous powder to melt into glass again.The effects of different parameters on the properties of the luminescent glass,such as H₃BO₃ and luminescent powder concentration,melting temperature and holding time,all of these were studied by experimental characterization,for instance,fluorescence spectroscopy,diffuse reflectance spectroscopy and near-edge X-ray absorption spectroscopy.The following conclusions could be drawn as flows:The results of X-ray diffraction analysis show that SrAl₂O₄: Eu²⁺,Dy³⁺?emission wavelength: 520nm?and Sr₄Al₁₄O₂₅: Eu²⁺,Dy³⁺?emission wavelength: 490nm?contained in the strontium aluminate phase.Which was the same in the luminous glass,that proved the composition of the strontium aluminate phase did not change.With the change of experimental conditions,the proportion of these components in the glass would change.The effect of on luminescence properties of luminous glass attributed to strontium aluminate phosphors was studied.An excessively high concentration of strontium aluminate powder resulted in the reduced luminous intensity in the glass and the deteriorated transparency.The mass ratio of the powder concentration was selected between 3% and 7% of powder concentration,originally the luminous intensity of glass increased with the mixed concentration of phosphor,but when the mass ratio of strontium aluminate powder in the glass was more than 5%,the luminescence intensity declined.Therefore,the concentration of strontium aluminate powder in the glass matrix should not exceed the mass ratio of 5%.The characterization about the concentration of H₃BO₃ in the glass matrix,influenced the properties of luminous glass.It was found that the luminous intensity of luminous glass firstly promoted when the concentration of H₃BO₃ improved,when the chemical molar ratio was more than 5%,the luminous intensity decreased.what's more,accompanied by the variable concentration,there would have the red shift phenomenon of PL performance.Melting temperature had an important impact on the performance of luminous glass.With the increase of sintering temperature,the transparency of glass would be optimized,the intensity of luminescence increased at first,then decreased.At the same time,the luminescence wavelength shifted to shorter.The optimum melting temperature was at 750 degrees Celsius.The luminous intensity of luminous glass was accompanied by the holding time during the sintering process.It decreased exponentially with the extension of holding time,and the emission peak position changed over time.The research on environment-related stability illustrated that under the same exposure environment,the performance of persistent luminescent glass had little change,while the luminous performance of the powder degenerated obviously.