In this study, down-conversion fluorescent powder of Sr2ZnSi2O7：Eu-（2＋）,Dy-（3＋）, SrAl2O4：Eu-（2＋）,Dy-（3＋） and Y2O2S：Eu-（3＋）,Mg-（2＋）,Ti-（4＋）, which were the common three primary colors materials ...In this study, down-conversion fluorescent powder of Sr2ZnSi2O7：Eu-（2＋）,Dy-（3＋）, SrAl2O4：Eu-（2＋）,Dy-（3＋） and Y2O2S：Eu-（3＋）,Mg-（2＋）,Ti-（4＋）, which were the common three primary colors materials with long afterglow, were synthesized by high temperature solid state method. The blends of rare earth（RE） luminescent materials have been of interest to reinvest the luminescent characteristics of polyethylene terephtahalate（PET） luminous fiber. The scanning electron microscopy（SEM） and an inversion fluorescence microscope were used to characterize the surface morphology and the dispersion of inclusion. Through analysis of microcosmic morphology, three typical dispersions of luminescent particles were summarized. The X-ray diffraction indicated that the phase structure of fiber samples and crystal structure of luminescence materials kept complete after prilling and spinning. From the fluorescence spectra and CIE 1931 coordinates, it could be found that different combinations of luminous fibers were desired to obtain divers colors emission luminous fiber. And the fiber samples were a light sensation which could induct different excitation wavelengths and convert it down to different colors. The afterglow decay curve and its differential curve were summarized indicating the three decay stages. The decay curve and decay rate curve showed that the contents of Sr2ZnSi2O7：Eu-（2＋）,Dy-（3＋）, SrAl2O4：Eu-（2＋）,Dy-（3＋） and Y2O2S：Eu-（3＋）,Mg-（2＋）,Ti-（4＋） had obvious influence on the afterglow of fiber samples.展开更多
Herein,we reported novel Y_(4)GeO_(8):Er^(3+),Yb^(3+)phosphors elaborated via conventional solid-state reaction.and we further explored their properties as optical thermometer by using fluorescence intensity ratio(FIR...Herein,we reported novel Y_(4)GeO_(8):Er^(3+),Yb^(3+)phosphors elaborated via conventional solid-state reaction.and we further explored their properties as optical thermometer by using fluorescence intensity ratio(FIR)method complemented by detailed analysis on crystal structure,up-conversion luminescence and energy transfer from Yb^(3+)to Er^(3+).Upon 980 nm laser excitation,Y_(4)GeO_(8):Er^(3+),Yb^(3+)phosphors present525,547 and 659 nm emission bands assigned to the characteristic transitions of Er^(3+).Furthermore,Y_(4)GeO_(8):Er^(3+),Yb^(3+)samples show outstanding temperature sensing performances.To be specific,the minimal temperature resolution is 0.03 K(303 K),and the relative sensitivity of FIR can be up to 1.152%/K(303 K).Hence,Y_(4)GeO_(8):Er^(3+),Yb^(3+)phosphors can be possible candidates for thermometry devices.展开更多
The cerium conversion film was applied to improving the corrosion resistance of Mg-Gd-Y-Zr magnesium alloy. The film was electrodeposited on the surface of the Mg-RE alloy in cerium nitrate solution. The compositions ...The cerium conversion film was applied to improving the corrosion resistance of Mg-Gd-Y-Zr magnesium alloy. The film was electrodeposited on the surface of the Mg-RE alloy in cerium nitrate solution. The compositions and morphologies were analyzed by X-ray diffraction(XRD), scanning election microscopy (SEM). The corrosion behaviors of the film were investigated electrochemical impedance spectroscopy (EIS), potentiodynamic polarization tests and immersion tests. The results show that the optimum parameters for electrochemical deposition are as follows: pH 10.0, time 30 min, 50 mmol/L Na2CO3 and temperature 25 ℃ by the designed experiments according to the orthogonal table L(9, 34). The corrosion protection efficiency is dependent on the deposition parameters. The cerium conversion film shows better corrosion protection behavior than chromate conversion film on Mg-Gd-Y-Zr magnesium alloy.展开更多
实现高发光效率、高亮度和良好的热稳定性是固态照明的迫切要求。因此,用于高功率发光二极管或激光二极管(LED/LD)的高性能荧光转换材料具有重要的研究意义。在这项工作中,通过将Lu^(3+)离子引入YAG∶Ce荧光陶瓷中方法作为有效策略来改...实现高发光效率、高亮度和良好的热稳定性是固态照明的迫切要求。因此,用于高功率发光二极管或激光二极管(LED/LD)的高性能荧光转换材料具有重要的研究意义。在这项工作中,通过将Lu^(3+)离子引入YAG∶Ce荧光陶瓷中方法作为有效策略来改善YAG∶Ce荧光材料的发光性能。采用固相反应和真空烧结法制Article ID:1000-7032(2023)06-0964^(-1)1收稿日期:2022^(-1)2-31;修订日期:2023-01-30基金项目:中国科学院战略性先导科技专项(XDA22010301)Supported by The Strategic Priority Research Program of The Chinese Academy of Sciences(XDA22010301)第6 HUANG Xinyou期,et al.:LuYAG∶Ce Transparent Ceramic Phosphors for High-brightness Solid-state…备了不同Lu^(3+)含量的(Lu,Y)_(3)Al_(5)O_(12)∶Ce荧光陶瓷(LuYAG∶Ce荧光陶瓷)。随着Lu^(3+)含量的增加,LuYAG∶Ce荧光陶瓷中的Y^(3+)位点被Lu^(3+)位点取代,Ce^(3+)的发射峰呈现从573 nm到563 nm的蓝移现象。当Lu^(3+)含量为60%时,通过将LuYAG∶Ce荧光陶瓷与蓝光LED组合,其发光强度达到最大值,流明效率达到114 lm∙W^(-1)。使用450 nm激光源与LuYAG∶Ce荧光陶瓷构建了透射模式下的激光驱动照明装置。随着功率密度从2.2 W·mm^(-2)增加到39 W·mm^(-2),Lu^(3+)含量为60%的荧光陶瓷光通量从128 lm增加到1874 lm,且没有发光饱和的迹象,最佳发光效率达到128 lm·W^(-1)。因此,LuYAG∶Ce荧光陶瓷有望成为高功率LED/LD照明的潜在荧光转换材料。展开更多
基金Project supported by the National Natural Science Foundation of China(51503082)the Fundamental Research Funds for the Central Universities(JUSRP51505,JUSRP116020)Jiangsu Province Ordinary University Academic Degree Graduate Student Scientific Research Innovation Projects(KYLX16-0791)
文摘In this study, down-conversion fluorescent powder of Sr2ZnSi2O7：Eu-（2＋）,Dy-（3＋）, SrAl2O4：Eu-（2＋）,Dy-（3＋） and Y2O2S：Eu-（3＋）,Mg-（2＋）,Ti-（4＋）, which were the common three primary colors materials with long afterglow, were synthesized by high temperature solid state method. The blends of rare earth（RE） luminescent materials have been of interest to reinvest the luminescent characteristics of polyethylene terephtahalate（PET） luminous fiber. The scanning electron microscopy（SEM） and an inversion fluorescence microscope were used to characterize the surface morphology and the dispersion of inclusion. Through analysis of microcosmic morphology, three typical dispersions of luminescent particles were summarized. The X-ray diffraction indicated that the phase structure of fiber samples and crystal structure of luminescence materials kept complete after prilling and spinning. From the fluorescence spectra and CIE 1931 coordinates, it could be found that different combinations of luminous fibers were desired to obtain divers colors emission luminous fiber. And the fiber samples were a light sensation which could induct different excitation wavelengths and convert it down to different colors. The afterglow decay curve and its differential curve were summarized indicating the three decay stages. The decay curve and decay rate curve showed that the contents of Sr2ZnSi2O7：Eu-（2＋）,Dy-（3＋）, SrAl2O4：Eu-（2＋）,Dy-（3＋） and Y2O2S：Eu-（3＋）,Mg-（2＋）,Ti-（4＋） had obvious influence on the afterglow of fiber samples.
基金Project supported by National Natural Science Foundation of China(11974315)Guangdong Science and Technology Innovation Strategy Foundation of China(20190310)。
文摘Herein,we reported novel Y_(4)GeO_(8):Er^(3+),Yb^(3+)phosphors elaborated via conventional solid-state reaction.and we further explored their properties as optical thermometer by using fluorescence intensity ratio(FIR)method complemented by detailed analysis on crystal structure,up-conversion luminescence and energy transfer from Yb^(3+)to Er^(3+).Upon 980 nm laser excitation,Y_(4)GeO_(8):Er^(3+),Yb^(3+)phosphors present525,547 and 659 nm emission bands assigned to the characteristic transitions of Er^(3+).Furthermore,Y_(4)GeO_(8):Er^(3+),Yb^(3+)samples show outstanding temperature sensing performances.To be specific,the minimal temperature resolution is 0.03 K(303 K),and the relative sensitivity of FIR can be up to 1.152%/K(303 K).Hence,Y_(4)GeO_(8):Er^(3+),Yb^(3+)phosphors can be possible candidates for thermometry devices.
基金Project (5133001E) supported by the Major State Basic Research and Development Program of China
文摘The cerium conversion film was applied to improving the corrosion resistance of Mg-Gd-Y-Zr magnesium alloy. The film was electrodeposited on the surface of the Mg-RE alloy in cerium nitrate solution. The compositions and morphologies were analyzed by X-ray diffraction(XRD), scanning election microscopy (SEM). The corrosion behaviors of the film were investigated electrochemical impedance spectroscopy (EIS), potentiodynamic polarization tests and immersion tests. The results show that the optimum parameters for electrochemical deposition are as follows: pH 10.0, time 30 min, 50 mmol/L Na2CO3 and temperature 25 ℃ by the designed experiments according to the orthogonal table L(9, 34). The corrosion protection efficiency is dependent on the deposition parameters. The cerium conversion film shows better corrosion protection behavior than chromate conversion film on Mg-Gd-Y-Zr magnesium alloy.
文摘实现高发光效率、高亮度和良好的热稳定性是固态照明的迫切要求。因此,用于高功率发光二极管或激光二极管(LED/LD)的高性能荧光转换材料具有重要的研究意义。在这项工作中,通过将Lu^(3+)离子引入YAG∶Ce荧光陶瓷中方法作为有效策略来改善YAG∶Ce荧光材料的发光性能。采用固相反应和真空烧结法制Article ID:1000-7032(2023)06-0964^(-1)1收稿日期:2022^(-1)2-31;修订日期:2023-01-30基金项目:中国科学院战略性先导科技专项(XDA22010301)Supported by The Strategic Priority Research Program of The Chinese Academy of Sciences(XDA22010301)第6 HUANG Xinyou期,et al.:LuYAG∶Ce Transparent Ceramic Phosphors for High-brightness Solid-state…备了不同Lu^(3+)含量的(Lu,Y)_(3)Al_(5)O_(12)∶Ce荧光陶瓷(LuYAG∶Ce荧光陶瓷)。随着Lu^(3+)含量的增加,LuYAG∶Ce荧光陶瓷中的Y^(3+)位点被Lu^(3+)位点取代,Ce^(3+)的发射峰呈现从573 nm到563 nm的蓝移现象。当Lu^(3+)含量为60%时,通过将LuYAG∶Ce荧光陶瓷与蓝光LED组合,其发光强度达到最大值,流明效率达到114 lm∙W^(-1)。使用450 nm激光源与LuYAG∶Ce荧光陶瓷构建了透射模式下的激光驱动照明装置。随着功率密度从2.2 W·mm^(-2)增加到39 W·mm^(-2),Lu^(3+)含量为60%的荧光陶瓷光通量从128 lm增加到1874 lm,且没有发光饱和的迹象,最佳发光效率达到128 lm·W^(-1)。因此,LuYAG∶Ce荧光陶瓷有望成为高功率LED/LD照明的潜在荧光转换材料。
