Tri-doped Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+),Tb^(3+),Mn^(2+)phosphors were prepared by a high-temperature solid state method.Under UV light excitation,Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+)samples exhibit a broad band r...Tri-doped Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+),Tb^(3+),Mn^(2+)phosphors were prepared by a high-temperature solid state method.Under UV light excitation,Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+)samples exhibit a broad band ranging from 320 to 500 nm.At 77 K,the emission spectra of Ca_(9)LiY_(2/3)(PO_(4))7:Ce^(3+)samples present two obvious emission peaks,indicating that Ce^(3+)ions occupy two different kinds of lattice sites(Ca(1/2)and Ca(3)),As a good sensitizer for Tb^(3+),Ce^(3+)ions in Ca_(9)LiY_(2/3)(PO_(4))_(7)lattice can effectively transfer part of energy to Tb^(3+),and the energy trans fer mechanism is determined to be dipole-dipole interaction.Consequently,the emitting color for Ce^(3+)and Tb^(3+)co-doped Ca_(9)LiY_(2/3)(PO_(4))_(7)samples can be tuned from bluish violet to green.In order to further enlarge the emission gamut,Mn^(2+)ions as red emission components were added,forming tri-doped single-phase Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+),Tb^(3+),Mn^(2+)phosphors.The Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+),Tb^(3+),Mn^(2+)phosphors exhibit tunable emission properties through controlling the relative doping concentration of Ce^(3+),Tb^(3+)and Mn^(2+).Especially,Ca_(9)LiY_(2/3)(PO_(4))_(7):0.09 Ce^(3+),0.12 Tb^(3+),0.30 Mn^(2+)can emit warm white light.The sample shows good thermal stability.At 150℃,the emission intensity for Ce^(3+)(360 nm),Tb^(3+)(545 nm)and Mn^(2+)(655 nm)decreases to 63%,69%,and 72%of its initial intensity,respectively.Moreover,the sample obtains good stability after 10 cycles between room temperature and150℃.展开更多
A series of Ca10Na(PO4)7:Ce3+/Tb3+/Mn2+(CNPO:Ce3+/Tb3+/Mn2+) phosphors with high brightness were synthesized by high-temperature solid-state method. X-ray diffraction(XRD), scanning electron microscopy(SEM), diffuse r...A series of Ca10Na(PO4)7:Ce3+/Tb3+/Mn2+(CNPO:Ce3+/Tb3+/Mn2+) phosphors with high brightness were synthesized by high-temperature solid-state method. X-ray diffraction(XRD), scanning electron microscopy(SEM), diffuse reflectance spectra(DRS), photo luminescence(PL) spectra, luminescence decay curves and thermally stability were performed to characterize the as-prepared samples. For Ce3+-doped samples, an intense and broad band emission is present under 265 nm excitation. When Ce3+and Tb3+are codoped, energy transfer(ET) process from Ce3+ to Tb3+ is demonstrated with electric dipole-dipole interaction. The internal and external quantum efficiencies(QEs) of CNPO:0.15 Ce3+, 0.04 Tb3+, 0.005 Mn2+are measured to 76.79% and 54.11% under 265 nm excitation and temperature-dependent PL intensity can remain 51.78% at 150 ℃ of its initial intensity at 25 ℃. It is indicated that single-phased white lightemitting CNPO:Ce3+/Tb3+/Mn2+phosphor can serve as a promising phosphor for illumination devices.展开更多
At present,the rare earth(RE) ions doped phosphors have attracted more and more attention because of their excellent properties.In this paper,a series of novel blue-purple β-Ca_(3)(PO_(4))_(2):Ce^(3+) phosphors were ...At present,the rare earth(RE) ions doped phosphors have attracted more and more attention because of their excellent properties.In this paper,a series of novel blue-purple β-Ca_(3)(PO_(4))_(2):Ce^(3+) phosphors were synthesized by a high temperature solid phase method.The X-ray diffraction(XRD),infrared spectrum,energy dispersive spectroscopy(EDS),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),photoluminescence excitation and emission spectra were used to investigate the crystal structure,composition and the luminescent properties of the resulting samples.The phosphor shows a strong absorption in the ultraviolet band.Under the excitation of 269 nm,the phosphor emits a strong purple fluorescence ranging from 360 to 520 nm.When Ce^(3+) doping content is 0.07 mol,the strongest luminescence intensity is reached,and the concentration quenching mechanism is dipole-dipole(d-d)interaction for Ce^(3+) based on Dexter theory.展开更多
基金Project supported by the National Natural Science Foundation of China(51672265)the Natural Science Foundation of Shandong Province(ZR2018JL016)+1 种基金the Applied Basic Research Plan of Qingdao(18-2-2-15-jch)the Open Funds of the State Key Laboratory of Rare Earth Resource Utilization(RERU2019003)。
文摘Tri-doped Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+),Tb^(3+),Mn^(2+)phosphors were prepared by a high-temperature solid state method.Under UV light excitation,Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+)samples exhibit a broad band ranging from 320 to 500 nm.At 77 K,the emission spectra of Ca_(9)LiY_(2/3)(PO_(4))7:Ce^(3+)samples present two obvious emission peaks,indicating that Ce^(3+)ions occupy two different kinds of lattice sites(Ca(1/2)and Ca(3)),As a good sensitizer for Tb^(3+),Ce^(3+)ions in Ca_(9)LiY_(2/3)(PO_(4))_(7)lattice can effectively transfer part of energy to Tb^(3+),and the energy trans fer mechanism is determined to be dipole-dipole interaction.Consequently,the emitting color for Ce^(3+)and Tb^(3+)co-doped Ca_(9)LiY_(2/3)(PO_(4))_(7)samples can be tuned from bluish violet to green.In order to further enlarge the emission gamut,Mn^(2+)ions as red emission components were added,forming tri-doped single-phase Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+),Tb^(3+),Mn^(2+)phosphors.The Ca_(9)LiY_(2/3)(PO_(4))_(7):Ce^(3+),Tb^(3+),Mn^(2+)phosphors exhibit tunable emission properties through controlling the relative doping concentration of Ce^(3+),Tb^(3+)and Mn^(2+).Especially,Ca_(9)LiY_(2/3)(PO_(4))_(7):0.09 Ce^(3+),0.12 Tb^(3+),0.30 Mn^(2+)can emit warm white light.The sample shows good thermal stability.At 150℃,the emission intensity for Ce^(3+)(360 nm),Tb^(3+)(545 nm)and Mn^(2+)(655 nm)decreases to 63%,69%,and 72%of its initial intensity,respectively.Moreover,the sample obtains good stability after 10 cycles between room temperature and150℃.
基金supported by National Natural Science Foundation of China(51302182)Natural Science Foundation of Shanxi Province(201601d011030)
文摘A series of Ca10Na(PO4)7:Ce3+/Tb3+/Mn2+(CNPO:Ce3+/Tb3+/Mn2+) phosphors with high brightness were synthesized by high-temperature solid-state method. X-ray diffraction(XRD), scanning electron microscopy(SEM), diffuse reflectance spectra(DRS), photo luminescence(PL) spectra, luminescence decay curves and thermally stability were performed to characterize the as-prepared samples. For Ce3+-doped samples, an intense and broad band emission is present under 265 nm excitation. When Ce3+and Tb3+are codoped, energy transfer(ET) process from Ce3+ to Tb3+ is demonstrated with electric dipole-dipole interaction. The internal and external quantum efficiencies(QEs) of CNPO:0.15 Ce3+, 0.04 Tb3+, 0.005 Mn2+are measured to 76.79% and 54.11% under 265 nm excitation and temperature-dependent PL intensity can remain 51.78% at 150 ℃ of its initial intensity at 25 ℃. It is indicated that single-phased white lightemitting CNPO:Ce3+/Tb3+/Mn2+phosphor can serve as a promising phosphor for illumination devices.
基金Project supported by the National Natural Science Foundation of China(41802040)China Postdoctoral International Exchange Program(2019.92)。
文摘At present,the rare earth(RE) ions doped phosphors have attracted more and more attention because of their excellent properties.In this paper,a series of novel blue-purple β-Ca_(3)(PO_(4))_(2):Ce^(3+) phosphors were synthesized by a high temperature solid phase method.The X-ray diffraction(XRD),infrared spectrum,energy dispersive spectroscopy(EDS),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),photoluminescence excitation and emission spectra were used to investigate the crystal structure,composition and the luminescent properties of the resulting samples.The phosphor shows a strong absorption in the ultraviolet band.Under the excitation of 269 nm,the phosphor emits a strong purple fluorescence ranging from 360 to 520 nm.When Ce^(3+) doping content is 0.07 mol,the strongest luminescence intensity is reached,and the concentration quenching mechanism is dipole-dipole(d-d)interaction for Ce^(3+) based on Dexter theory.
