以Ca-Si-Al-O玻璃为主要原料,通过添加Eu_2O_3,采用碳热还原氮化法合成出Ca-α-Si Al ON∶Eu荧光粉体。借助X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外-可见分光光度计和荧光分光光度计等手段,对合成Ca-α-Si Al ON∶Eu的物相组成、...以Ca-Si-Al-O玻璃为主要原料,通过添加Eu_2O_3,采用碳热还原氮化法合成出Ca-α-Si Al ON∶Eu荧光粉体。借助X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外-可见分光光度计和荧光分光光度计等手段,对合成Ca-α-Si Al ON∶Eu的物相组成、显微结构及发光性能进行表征。结果表明:(1)以Ca O,Al_2O_3,Si O_2为原料,合成的Ca-SiAl-O非晶玻璃具有Si O4四面体与Al O4四面体相互连接的架状结构;(2)以Ca-Si-Al-O玻璃为主要原料,通过添加Eu_2O_3,在1450℃碳热还原氮化合成出呈棱柱状形貌的Ca-α-Si Al ON粉体,其中Eu离子在Ca-α-Si Al ON中实现了良好的固溶;(3)合成的Ca-α-Si Al ON∶Eu在紫外-可见光部分具有较强的吸收,在420 nm的激发下,发射光谱的峰值波长为~570 nm,实现了黄绿光发射,归属于Eu^(2+)的4f^65d-4f^7跃迁。展开更多
Nitrogen-rich Ca-α-sialon： Eu2＋ phosphors with saturated calcium solubility are synthesized through a solid- state reaction （SSR） at 2173 K with stable alloy and nitride as the starting materials. The Ca1.83-1.sx...Nitrogen-rich Ca-α-sialon： Eu2＋ phosphors with saturated calcium solubility are synthesized through a solid- state reaction （SSR） at 2173 K with stable alloy and nitride as the starting materials. The Ca1.83-1.sxSi8.34 A13.66 Ox N16-x： xEu phosphors have intensive orange emissions, whose peaks are located at approximately 585 600 nm, and the emission wavelengths tend to shift toward the red region when the Eu concentrations increase from 0.5% to 18% （mole percentage）. When the Eu concentration is equal to 9%, the phosphors suffer from concentration quenching. The low-temperature photoluminescence properties indicate that Cal.aa-l.5xSi8.34Ala.66OzN16-x： xEu phosphors show ex- cellent thermal quenching. The crystal structures of Cal.83-1.5xSis.34A13.660xN16-x： xEu are also investigated, and are found to have nitrogen-rich compositions with saturated calcium cations at the interstitial sites of the α-sialons. In addition, tile influencing factors of α-sialons with different compositions on the crystal lattice are discussed in detail.展开更多
采用一种保温辅助(TIA)的燃烧合成工艺,高效、快捷地制备出了高性能Eu^(2+)掺杂的Ca-α-Si Al ON荧光粉。在传统的燃烧合成工艺的基础上,在反应物原料的外部包裹氮化硅保温层,显著阻碍了燃烧过程中的热量散失,使体系处于高温反应区的时...采用一种保温辅助(TIA)的燃烧合成工艺,高效、快捷地制备出了高性能Eu^(2+)掺杂的Ca-α-Si Al ON荧光粉。在传统的燃烧合成工艺的基础上,在反应物原料的外部包裹氮化硅保温层,显著阻碍了燃烧过程中的热量散失,使体系处于高温反应区的时间延长至原有工艺的3倍以上,从而促进了晶体的充分生长和发育。通过使用XRD、SEM、PL光谱等测试手段对产物进行全面分析,发现在使用了氮化硅保温层的样品中,产物为纯相的Ca-α-Si Al ON,颗粒的结晶良好,呈现等轴状形貌,粒径分布均匀。PL光谱测试表明,其在250~350 nm和350~450 nm区间内存在2个较宽的吸收带,在568 nm附近处有较强的黄光发射。包裹了氮化硅保温层后,产物的荧光性能有了明显改进,激发光谱和发射光谱的强度均有显著提高。展开更多
Eu-doped Ca-α-SiAlON yellow phosphors, with the compositions Ca0.72Eu0.08Si9.56Al2.44O0.84N15.16, were prepared by a highly efficient combustion synthesis method. By optimizing the starting compositions of reactants ...Eu-doped Ca-α-SiAlON yellow phosphors, with the compositions Ca0.72Eu0.08Si9.56Al2.44O0.84N15.16, were prepared by a highly efficient combustion synthesis method. By optimizing the starting compositions of reactants and choosing appropriate post-annealing conditions, phase-pure, uniform and fine Ca-α-sialon：Eu2＋ phosphors possessing the particle size ranging -3-5μm, and good luminescence properties with an intense emission band that peaks at 592 nm under n-UV or blue light excitation were ob-tained. The results indicated that combustion synthesis method was an energy efficient, time saving and low cost way to prepare Ca-α-SiAlON phosphors by controlling the mass ratio of comburents. A combination with post-annealing treatment was desired for further increase of the properties of Ca-α-SiAlON phosphors.展开更多
文摘以Ca-Si-Al-O玻璃为主要原料,通过添加Eu_2O_3,采用碳热还原氮化法合成出Ca-α-Si Al ON∶Eu荧光粉体。借助X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外-可见分光光度计和荧光分光光度计等手段,对合成Ca-α-Si Al ON∶Eu的物相组成、显微结构及发光性能进行表征。结果表明:(1)以Ca O,Al_2O_3,Si O_2为原料,合成的Ca-SiAl-O非晶玻璃具有Si O4四面体与Al O4四面体相互连接的架状结构;(2)以Ca-Si-Al-O玻璃为主要原料,通过添加Eu_2O_3,在1450℃碳热还原氮化合成出呈棱柱状形貌的Ca-α-Si Al ON粉体,其中Eu离子在Ca-α-Si Al ON中实现了良好的固溶;(3)合成的Ca-α-Si Al ON∶Eu在紫外-可见光部分具有较强的吸收,在420 nm的激发下,发射光谱的峰值波长为~570 nm,实现了黄绿光发射,归属于Eu^(2+)的4f^65d-4f^7跃迁。
基金Project supported by the National Natural Science Foundation of China (Grant No. 90922027)the National High Technology Research and Development Program of China (Grant No. 2009AA03Z432)the Doctoral Fund of Ministry of China (Grant No. 20100006110011)
文摘Nitrogen-rich Ca-α-sialon： Eu2＋ phosphors with saturated calcium solubility are synthesized through a solid- state reaction （SSR） at 2173 K with stable alloy and nitride as the starting materials. The Ca1.83-1.sxSi8.34 A13.66 Ox N16-x： xEu phosphors have intensive orange emissions, whose peaks are located at approximately 585 600 nm, and the emission wavelengths tend to shift toward the red region when the Eu concentrations increase from 0.5% to 18% （mole percentage）. When the Eu concentration is equal to 9%, the phosphors suffer from concentration quenching. The low-temperature photoluminescence properties indicate that Cal.aa-l.5xSi8.34Ala.66OzN16-x： xEu phosphors show ex- cellent thermal quenching. The crystal structures of Cal.83-1.5xSis.34A13.660xN16-x： xEu are also investigated, and are found to have nitrogen-rich compositions with saturated calcium cations at the interstitial sites of the α-sialons. In addition, tile influencing factors of α-sialons with different compositions on the crystal lattice are discussed in detail.
文摘采用一种保温辅助(TIA)的燃烧合成工艺,高效、快捷地制备出了高性能Eu^(2+)掺杂的Ca-α-Si Al ON荧光粉。在传统的燃烧合成工艺的基础上,在反应物原料的外部包裹氮化硅保温层,显著阻碍了燃烧过程中的热量散失,使体系处于高温反应区的时间延长至原有工艺的3倍以上,从而促进了晶体的充分生长和发育。通过使用XRD、SEM、PL光谱等测试手段对产物进行全面分析,发现在使用了氮化硅保温层的样品中,产物为纯相的Ca-α-Si Al ON,颗粒的结晶良好,呈现等轴状形貌,粒径分布均匀。PL光谱测试表明,其在250~350 nm和350~450 nm区间内存在2个较宽的吸收带,在568 nm附近处有较强的黄光发射。包裹了氮化硅保温层后,产物的荧光性能有了明显改进,激发光谱和发射光谱的强度均有显著提高。
基金Project supported by the National Natural Science Foundation of China(51302311)the National High Technology Research and Development Program of China(2009AA03Z211)
文摘Eu-doped Ca-α-SiAlON yellow phosphors, with the compositions Ca0.72Eu0.08Si9.56Al2.44O0.84N15.16, were prepared by a highly efficient combustion synthesis method. By optimizing the starting compositions of reactants and choosing appropriate post-annealing conditions, phase-pure, uniform and fine Ca-α-sialon：Eu2＋ phosphors possessing the particle size ranging -3-5μm, and good luminescence properties with an intense emission band that peaks at 592 nm under n-UV or blue light excitation were ob-tained. The results indicated that combustion synthesis method was an energy efficient, time saving and low cost way to prepare Ca-α-SiAlON phosphors by controlling the mass ratio of comburents. A combination with post-annealing treatment was desired for further increase of the properties of Ca-α-SiAlON phosphors.
