Effects of aluminum co-doping on photoluminescence properties of Ce^(3+)-doped SiO_2 glasses  

作　　者：LF KOAO H.C.SWART F.B.DEJENE 

机构地区：[1]Department of Physics,University of the Free State(Qwaqwa Campus),Private Bag X13,Phuthaditjhaba,9866,South Africa [2]Department of Physics,University of the Free State,P.O.Box 339,Bloemfontein,9300,South Africa

出　　处：《Journal of Rare Earths》2010年第S1期206-210,共5页稀土学报（英文版）

基　　金：the National Research Foundation and the University of the Free Statefor financial support

摘　　要：SiO2 glasses co-doped with Al3+ ions were prepared by a sol-gel method by holding 0.5% of Ce3+ ions constant and varying the Al3+ ions concentrations.Thermal stability,the structural,chemical and the optical properties of the samples were studied by using differential scanning calorimetric(DSC),thermo gravimetric analysis(TGA),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),UV-vis spectroscopy and photoluminescence spectroscopy(PL).The DSC and TGA of samples depicted that the presence of dopant and co-dopant decreased the endothermic peak temperature and the yield respectively.SEM images showed that the particles were in the nano-range and spherical in shape.The XRD showed that all the samples were amorphous.The UV absorption measurements indicated that the presence of Al3+ ions significantly reduced the SiO2 absorption band,increased the absorbance intensity of SiO2 and decreased the transmittance as compared to the presence of the Ce3+ ions alone.The photoluminescence results displayed an optimum increase in luminescence intensity when the ratio of Al:Ce was 10:1 and further increase in aluminum content quenched the luminous intensity.SiO2 glasses co-doped with Al3+ ions were prepared by a sol-gel method by holding 0.5% of Ce3+ ions constant and varying the Al3+ ions concentrations.Thermal stability,the structural,chemical and the optical properties of the samples were studied by using differential scanning calorimetric(DSC),thermo gravimetric analysis(TGA),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),UV-vis spectroscopy and photoluminescence spectroscopy(PL).The DSC and TGA of samples depicted that the presence of dopant and co-dopant decreased the endothermic peak temperature and the yield respectively.SEM images showed that the particles were in the nano-range and spherical in shape.The XRD showed that all the samples were amorphous.The UV absorption measurements indicated that the presence of Al3+ ions significantly reduced the SiO2 absorption band,increased the absorbance intensity of SiO2 and decreased the transmittance as compared to the presence of the Ce3+ ions alone.The photoluminescence results displayed an optimum increase in luminescence intensity when the ratio of Al:Ce was 10:1 and further increase in aluminum content quenched the luminous intensity.

关 键 词：SiO2:Ce Al when sol-gel molar ration NANO-SIZE LUMINESCENCE enhancement rare earths 

分 类 号：TQ171.71[化学工程—玻璃工业]