A series of Sr_(2)MgSi_(2)O_(7):Tb^(3+)nanophosphors is prepared using a high-temperature solid-state reaction.The x-ray diffraction patterns show that the crystal structure of the sample is not significantly affected...A series of Sr_(2)MgSi_(2)O_(7):Tb^(3+)nanophosphors is prepared using a high-temperature solid-state reaction.The x-ray diffraction patterns show that the crystal structure of the sample is not significantly affected by Tb^(3+)ions.However,the images of the scanning electron microscope illustrate that the average size of nanoparticles becomes larger with the increase of Tb^(3+)concentration.Unlike earlier investigations on down-conversion emission of Tb^(3+)ion excited by deep ultraviolet light,in this work,the photoluminescence characteristics of Sr_(2)MgSi_(2)O_(7)nanophosphors doped with different Tb^(3+)concentrations are analyzed under 374-nm excitations.The intense green emission at 545 nm is observed at an optimal doping concentration of 1.6 mol%.The main reason for the concentration quenching is due to the electric dipole-electric dipole interaction among Tb^(3+)ions.展开更多
Three alkaline earth silicate phosphors: Sr2MgSi2O7∶Eu, Dy, Gd, Sr3MgSi2O8∶Eu, Dy, Gd and Sr2MgSi2O7∶Eu, Dy were prepared and their luminescent properties were investigated. The Photoluminescence (PL) measurements ...Three alkaline earth silicate phosphors: Sr2MgSi2O7∶Eu, Dy, Gd, Sr3MgSi2O8∶Eu, Dy, Gd and Sr2MgSi2O7∶Eu, Dy were prepared and their luminescent properties were investigated. The Photoluminescence (PL) measurements indicated that the phosphors gave a longer emitting phosphorescence phenomenon by comparing with those without Gd2O3 activator, in which a better afterglow characteristic was observed by adding Gd2O3 to the phosphors. While little influence on the structure of luminescent materials was observed via XRD spectra, and obvious emission wavelength shift was exhibited due to the differences in the structure parameters of the two hosts. The results revealed that the improvement was due to nonequivalent substitution to produce more e-traps, and energy transfer from Gd3+ to Dy3+, to boost the performance of Sr2MgSi2O7∶Eu, Dy phosphor. Role of Gd3+ co-doped into Sr2MgSi2O7∶Eu, Dy matrix and the possible long-lasting phosphorescence progress were discussed.展开更多
In order to improve the red luminescent properties,Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)was selected as a blue persistent luminescent donor phosphor,while light conversion agent was utilized to tune the persistent lumin...In order to improve the red luminescent properties,Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)was selected as a blue persistent luminescent donor phosphor,while light conversion agent was utilized to tune the persistent luminescent spectra from blue to red.Composite red luminescent material Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)/light conversion agent(SMED/LCA)was fabricated with light conversion agent and Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)at a certain mass ratio.SiO_(2)(Al2 O_(3) or MgF2)were coated on the surface of SMED/LCA through heterogeneous deposition method.The structural and optical characteristics of the resulting samples were launched in terms of X-ray diffraction and emission spectrum as well as afterglow brightness.The results demonstrate that the emission spectrum exhibits two emission bands,and the peaks are located at around 470 and 615 nm.SiO_(2),Al_(2)O_(3) and MgF_(2) are coated on the surface of SMED/LCA like a protective shell to maintain its stability and luminescent properties,the afterglow initial brightness is still up to 0.37 cd/m^(2) and the afterglow color purity calculated from CIE color coordinates is basically unchanged.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11004092)the Foundation of Science and Technology Department of Liaoning Province,China(Grant No.201602455)。
文摘A series of Sr_(2)MgSi_(2)O_(7):Tb^(3+)nanophosphors is prepared using a high-temperature solid-state reaction.The x-ray diffraction patterns show that the crystal structure of the sample is not significantly affected by Tb^(3+)ions.However,the images of the scanning electron microscope illustrate that the average size of nanoparticles becomes larger with the increase of Tb^(3+)concentration.Unlike earlier investigations on down-conversion emission of Tb^(3+)ion excited by deep ultraviolet light,in this work,the photoluminescence characteristics of Sr_(2)MgSi_(2)O_(7)nanophosphors doped with different Tb^(3+)concentrations are analyzed under 374-nm excitations.The intense green emission at 545 nm is observed at an optimal doping concentration of 1.6 mol%.The main reason for the concentration quenching is due to the electric dipole-electric dipole interaction among Tb^(3+)ions.
基金the National Natural Science Foundation (20376009)the Liaoning Natural Science Foundation(20032129) of China
文摘Three alkaline earth silicate phosphors: Sr2MgSi2O7∶Eu, Dy, Gd, Sr3MgSi2O8∶Eu, Dy, Gd and Sr2MgSi2O7∶Eu, Dy were prepared and their luminescent properties were investigated. The Photoluminescence (PL) measurements indicated that the phosphors gave a longer emitting phosphorescence phenomenon by comparing with those without Gd2O3 activator, in which a better afterglow characteristic was observed by adding Gd2O3 to the phosphors. While little influence on the structure of luminescent materials was observed via XRD spectra, and obvious emission wavelength shift was exhibited due to the differences in the structure parameters of the two hosts. The results revealed that the improvement was due to nonequivalent substitution to produce more e-traps, and energy transfer from Gd3+ to Dy3+, to boost the performance of Sr2MgSi2O7∶Eu, Dy phosphor. Role of Gd3+ co-doped into Sr2MgSi2O7∶Eu, Dy matrix and the possible long-lasting phosphorescence progress were discussed.
基金Project supported by Natural Science Foundation of Jiangsu Province(BK20171140,BK20180629)National Natural Science Foundation of China(51803076)。
文摘In order to improve the red luminescent properties,Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)was selected as a blue persistent luminescent donor phosphor,while light conversion agent was utilized to tune the persistent luminescent spectra from blue to red.Composite red luminescent material Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)/light conversion agent(SMED/LCA)was fabricated with light conversion agent and Sr_(2)MgSi_(2)O_(7):Eu^(2+),Dy^(3+)at a certain mass ratio.SiO_(2)(Al2 O_(3) or MgF2)were coated on the surface of SMED/LCA through heterogeneous deposition method.The structural and optical characteristics of the resulting samples were launched in terms of X-ray diffraction and emission spectrum as well as afterglow brightness.The results demonstrate that the emission spectrum exhibits two emission bands,and the peaks are located at around 470 and 615 nm.SiO_(2),Al_(2)O_(3) and MgF_(2) are coated on the surface of SMED/LCA like a protective shell to maintain its stability and luminescent properties,the afterglow initial brightness is still up to 0.37 cd/m^(2) and the afterglow color purity calculated from CIE color coordinates is basically unchanged.
