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A novel white-light emitting CaAl2SiO6: Ce3+, Tb3+ phosphor has been prepared by a sol–gel method. X-ray diffractometry and spectrofluorometry were used to characterize structural and optical properties of the samples. The results indicate that the crystal structure of the phosphor is a single phase of CaAl2SiO6. The excitation band of the phosphor covers a wide region from 240 nm to 380 nm. CaAl2SiO6: Ce3+, Tb3+ phosphors show four emission bands: one at 400 nm for Ce3+ and three at 487 nm, 543 nm and 585 nm for Tb3+. With appropriate tuning of Tb3+ content, white light with different hues can be achieved under UV radiation. The energy transfer mechanism from Ce3+ to Tb3+ in CaAl2SiO6 host was demonstrated to be dipole–dipole interaction. 相似文献
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J. Sun J. Lai Z. Xia X. Zhang H. Liu H. Du 《Applied physics. B, Lasers and optics》2012,107(3):827-831
Novel green-emitting Ba2Y(BO3)2Cl:Ce3+,Tb3+ phosphors were synthesized by a solid-state method. X-ray diffraction and photoluminescence spectra were utilized to characterize the structures and luminescence properties of the as-synthesized phosphors, respectively. Ba2Y(BO3)2Cl:Ce3+,Tb3+ phosphors exhibit blue and green emission bands under the excitation of near-ultraviolet light. An asymmetric blue emission originates from the Ce3+ ion, whereas the green emission originates from the Tb3+ ion. A spectral overlap is found between the emission band of the Ce3+ ion and the excitation band of the Tb3+ ion, which supports the occurrence of the energy transfer from the Ce3+ ion to the Tb3+ ion. Meanwhile, the energy transfer is thoroughly investigated by their photoluminescence decay behaviors. The energy-transfer efficiency from the Ce3+ ion to the Tb3+ ion is also calculated, and a possible mechanism is proposed. 相似文献
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KAlF4:Ce,Tb磷光体的发光特性及Ce^3+对Tb^3+的敏化作用 总被引:3,自引:3,他引:3
采用溶液反应法和高温固相反应法合成了KA1F4基质化合物及KA1F:Ce,Tb磷光体,测定了磷光体的激发光谱和发射光谱,研究了在碱金属氟铝酸盐基质中Ce^3+对Tb^3+的能量传递,根据Ce^3+,Tb^3+在KAlF4中的能级关系,分析了其发光特性和Ce^3+对Tb^3+能量传递过程。 相似文献
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Ce3+ and Dy3+-doped LiAl5O8 were synthesized in the present study. The luminescence properties of Ce3+ and Dy3+, and the energy transfer from Ce3+ to Dy3+ were investigated. The Ce3+ species in LiAl5O8 emit one broad band that peaks at 351 nm under the excitation of ultraviolet light, which is attributed to the 5d–4f transitions of Ce3+. The luminescence of Dy3+ in singly doped LiAl5O8 can not be detected due to its low oscillator strength. However, Dy3+ emit intense blue (477 nm) and yellow (569 nm) light after the introduction of Ce3+. This phenomenon demonstrates that there exists effective energy transfer from Ce3+ to Dy3+, which occurs because the emission spectrum of Ce3+ perfectly overlays the excitation spectrum of Dy3+. The energy transfer from Ce3+ to Dy3+ is performed through dipole–dipole interactions. The experimental results show that LiAl5O8 co-doped with Ce3+ and Dy3+ can be a potential two-band (blue and yellow) phosphor. 相似文献
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采用高温固相法合成了BaZnP2 01:Eu2 ,Mn2 荧光粉,并对其发光性质及Eu2 对Mn2 的能量传递机理进行了研究.Eu2 和Mn2 在380 am和670 nm的发射峰分别由Eu2 的5d-14f跃迁和Mn2 的4T1(4G)-6A1(6S)跃迁产生.Eu2 对Mn2 的发光有很强的敏化作用,根据Dexter电多极相互作用的能量传递概率公式,判断出BaZnP2O7中Eu2 对Mn2 的能量传递属于电偶极-电四极相互作用引起的共振能量传递. 相似文献
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Wenyu Zhao Shengli An Bin Fan Songbo Li 《Applied Physics A: Materials Science & Processing》2013,111(2):601-604
Tb3+-doped Na3YSi2O7 phosphors were prepared by the sol–gel method and then characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy, and cathodoluminescence spectroscopy. The XRD results reveal that the Tb3+ ions have been introduced as dopants into the Na3YSi2O7 host lattice. Under low-voltage electron beam excitation, the phosphors exhibit the characteristic emissions of Tb3+ (5 D 3,4→7 F J , J=3–6 transitions). The luminescence color of the phosphors can be tuned from greenish-blue to bluish-green and to green by controlling the Tb3+ concentration within the 0.0005–0.15 (x value). The optimum Tb3+ doping concentration is 10 mol%, and the “dead voltage” is approximately 1.35 kV. All results indicate that the sample is a phosphor candidate for field-emission displays. 相似文献
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Ce3+, Tb3+ codoped amorphous calcium silicate phosphor was prepared by heating (830 °C for 30 min) Ce3+, Tb3+ codoped calcium silicate hydrate phosphor formed by liquid-phase reaction. The excitation peak wavelength of the resulting phosphor was 330 nm and the emission peak wavelengths were at 544 nm, attributed to the 5D4→7F5 transition of Tb3+, and at 430–470 mm, attributed to Ce3+. The intensity ratio of the two peaks could be freely controlled by varying the Tb/Ca atomic ratio of the Ce3+, Tb3+ codoped amorphous calcium silicate phosphor, allowing light to be emitted over a wide range from blue to green. It was clarified that energy transfer exists from Ce3+ to Tb3+. 相似文献
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Calcium metasilicate phosphors activated by Ce3+ and Tb3+ have been studied for their emission characteristics. In two series of phosphors, one activator was kept at its optimum value while the other was varied. In another two series, one activator was kept below its optimum value and the other was varied. Concentration quenching effects start when each activator gives its maximum emission. There is clear evidence of an energy transfer from Ce3+ to Tb3+ because the5 D 3 lines appear on addition of Ce3+ while they were conspicuously absent when Tb3+ alone was present. Their absence in singly activated phosphors could not have been due to cross-relaxation. Obviously X-ray excitation does not lead to5 D 3 transitions which are achieved only by energy transfer. Further, considering the features of the emission spectra and the concentrations of activators used, the transfer could only be of the dipole-dipole type. 相似文献
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Powder phosphors of CaLa1? x Eu x Al3O7, CaLa1? x Ce x Al3O7 and CaLa0.99? x Eu x Ce0.01Al3O7, where x = 0.01, 0.03, 0.05 and 0.07, were prepared by a combustion method. The powders were well characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence techniques. Emission spectra of Eu3+-doped powder phosphors showed strong red emission at 613 nm (5D0 → 7F2); no concentration quenching was observed. Generally, Ce3+ acts as an efficient sensitizer when doped with other trivalent lanthanide ions. However, interestingly, in the CaLaAl3O7 powder phosphors, the addition of Ce3+ with Eu3+ exhibited an adverse effect–decreased photoluminescence intensity. The reasons for this behavior are discussed. 相似文献
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采用溶液反应和固相反应,分别合成了KAIF4基质化合物及KAIF4:Gd、KAIF4:Ce,Gd等磷光体,研究了它们的光谱特性。结果表明,KAIF4:Gd无认顷皮或长波紫外辐激发下,均无任何吸收和发射。在KAIF4:Ce,Gd中,Ce^3+离子能有效地将能量传递给Gd^3+离子,使Gd^3+产生了特征锐发射,具发射强度很大。但当Ce^3+浓度固定不变,改变Gd^3+的^6P1/2→^8S7/2发射 相似文献
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Ce3+,Tb3+氟化物磷光体的发光性质比较 总被引:2,自引:1,他引:2
采用溶液反应和固相反应分别合成了K3AlF6基质化合物及KBF4:Ce,Tb和K3AlF6:Ce,Tb等磷光体,研究了它们的光谱特性,并与KAlF4:Ce,Tb、CaF2:Tb和AlF3:Ce,Tb等磷光体的发光特性进行了比较。结果发现,CaF2:Ce,Tb、AlF3:Ce,Tb、KBF4:Ce,Tb和K3AlF6:Ce,Tb等磷光体中Ce^3+对Tb^3+的能量传递不能有效进行,有时Tb^3+起 相似文献
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A several of LiLaSiO4: xTb3+, ySm3+ (LLSO) phosphors were synthesized by high-temperature solid-phase reaction. Through SEM, XRD and fluorescence spectrometer, the phase, morphology, luminescence properties and energy transfer of the samples were systematically analyzed and discussed. Under an excitation of 378 nm wavelength, LLSO: xTb3+ phosphors emit green light, and the concentration quenching point of Tb3+ ions was x = 0.08. In LLSO: xTb3+, ySm3+ phosphors, When Sm3+ ions doping molar mass fraction increases, the fluorescence intensity of Tb3+ ion decreases while the fluorescence intensity of Sm3+ ions first strengthen and then weaken. The concentration quenching point of Sm3+ ions was y = 0.04. By changing the proportion of Sm3+ and Tb3+ ions, the luminous color can be adjusted from green to red. There is effective energy transfer between Tb3+→Sm3+. The molar mass fraction of doping Sm3+ ions is y = 0.10, the energy transfer efficiency reaches 96.67%. The energy transfer mechanism is the quadrupole-quadrupole interaction. The quantum yield is 22.34%. Therefore, LLSO: xTb3+, ySm3+ phosphors have certain potential application value in the field of ultraviolet-near ultraviolet white LEDs. 相似文献
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Zhendong Hao Jiahua Zhang Xia Zhang Shaozhe Lu Yongshi Luo Xinguang Ren Xiaojun Wang 《Journal of luminescence》2008,128(5-6):941-944
α- and β-Ca2P2O7: Eu2+, Mn2+ phosphors were prepared by solid-state reaction. Phase transition from tetragonal (β-phase) to monoclinic (α-phase) is performed. A strong orange emission of Mn2+ is observed in both α-and β-Ca2P2O7: Eu2+, Mn2+ upon near ultraviolet (UV) excitation through energy transfer from Eu2+ to Mn2+. The transfer efficiencies for various Mn2+ concentrations are estimated based on lifetime measurements of the fluorescence of Eu2+ in the two phases. The photoluminescence excitation spectra of α-Ca2P2O7: Eu2+, Mn2+ can cover 400 nm of the near-UV range, denoting its potential use as a phosphor with intense orange component for white light emitting diodes (LEDs). 相似文献
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在本文中制作了CaAl4O7:Tb^3 ,Ce^3 新荧光材料。烧结温度为1300℃,烧结环境为N2+5%H2还原气。TEM实验结果表明样品的粒度小于1μm。X-射线和HRTEM实验证实,样品的晶格点阵十分规则,而且没有发现掺杂和助溶剂对基质结构的影响,表现出十分好的材料质量。光学实验观测到对应于Tb^3 离子的^5D4到^7FJ(J=6,5,4,3)的跃迁发射峰在485,545,590和630nm。CaAl4O7:Tb^3 ,Ce^3 降低了基质结构的不确定性,同时保持了Tb^3 发光中心的特性。 相似文献