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采用水热法制备出NaY(MoO4)2:Eu3+,Tb3+下转换发光材料。通过X射线粉末衍射、红外光谱、荧光激发和发射光谱对其进行表征。讨论了不同反应温度及Eu3+掺杂浓度对NaY(MoO4)2:Eu3+,Tb3+的晶体结构和发光性能的影响,得到水热温度为180℃及Eu3+浓度为摩尔分数0.7%时,样品具有最佳的发光效果。在395nm光激发下,观察到了591nm处橙光发射峰以及616nm处强红光发射峰,分别对应于Eu3+的5D0→7F1和5D0→7F2跃迁。并研究了NaY(MoO4)2:Eu3+,Tb3+材料中Tb3+对Eu3+的敏化作用及能量传递过程。 相似文献
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SrZn2(PO4)2:Sm3+ phosphor was synthesized by a high temperature solid-state reaction in atmosphere. SrZn2(PO4)2:Sm3+ phosphor is efficiently excited by ultraviolet (UV) and blue light, and the emission peaks are assigned to the transitions of 4G5/2-6H5/2 (563 nm), 4G5/2-6H7/2 (597 nm and 605 nm) and 4G5/2-6H9/2 (644 nm and 653 nm). The emission intensities of SrZn2(PO4)2:Sm3+ are influenced by Sm3+ concentration, and the concentration quenching effect of SrZn2(PO4)2:Sm3+ is also observed. When doping A+ (A=Li, Na and K) ions, the emission intensity of SrZn2(PO4)2:Sm3+ can be obviously enhanced. The Commission Internationale de l'Eclairage (CIE) color coordinates of SrZn2(PO4)2:Sm3+ locate in the orange-red region. The results indicate that the phosphor has a potential application in white light emitting diodes (LEDs). 相似文献
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YVO4:Ba2+ nanoparticles with a Ba2+ doping concentration x=0%, 1%, 3%, 5%, 7% and 9% were synthesized by a solvothermal method and then they were codoped with Eu3+ ions by an ion exchange method to form the YVO4:Eu3+,Ba2+ nanoparticles. It was found that the photoluminescence intensity of the as-prepared YVO4:Eu3+,Ba2+ nanoparticles steadily increased with x until x=7%, and then decreased for higher x. Thermal annealing resulted in considerable enhancement in their photoluminescence, and higher annealing temperature led to stronger photoluminescence enhancement. The emission intensity of the YVO4:Eu3+,Ba2+ (x=7%) nanoparticles annealed at 500 °C was about 205% stronger than the sample without Ba2+ doping. Thermal annealing of the ion-exchanged YVO4:Eu3+,Ba2+ nanoparticles at 500 °C and 700 °C resulted in photoluminescence enhancement of about 14 times and 27 times, respectively. The asymmetric ratio of Eu3+ in the ion-exchanged YVO4:Eu3+,Ba2+ nanoparticles was found to increase after annealing. 相似文献
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Blue emitting phosphor SrZn2(PO4)2:Eu2+ is synthesized by a high temperature solid state method, and the luminescent properties are investigated. At the 330 nm radiation excitation, SrZn2(PO4)2:Eu2+ presents an emission band at 416 nm, which is assigned to the 4f65d1→4f7 transition of Eu2+ ion. The concentration quenching effect of Eu2+ in SrZn2(PO4)2 has been validated and proved to be a resonant type via a dipole-dipole interaction. The critical distance (Rc) of Eu2+ in SrZn2(PO4)2 is calculated to be 3.244 nm. The Commission International de I’Eclairage (CIE) chromaticity coordinates of SrZn2(PO4)2:Eu2+ locate at the blue region, such as (0.150, 0.072). The results indicate that the SrZn2(PO4)2:Eu2+ phosphor may have potential applications in white light emitting diodes (LEDs). 相似文献
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A series of Tb^3+ doped Na Y(Mo O4)2 are synthesized by a solid-state reaction at 550 °C for 4 h, and their luminescent properties are investigated. The phase formation is carried out with X-ray powder diffraction analysis, and there is no other crystalline phase except Na Y(Mo O4)2. Na Y(Mo O4)2:Tb^3+ can produce the green emission under 290 nm radiation excitation, and the luminescence emission peak at 545 nm corresponds to the 5D4→7F5 transition of Tb^3+. The emission intensity of Tb^3+ in Na Y(Mo O4)2 is enhanced with the increase of Tb^3+ concentration, and there is no concentration quenching effect. The phenomena are proved by the decay curves of Tb^3+. Moreover, the Commission International de I'Eclairage(CIE) chromaticity coordinates of Na Y(Mo O4)2:Tb^3+ locate in the green region. 相似文献
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A series of Eu3+ or Tb3+ doped Ba2Ca(BO3)2 phosphors were synthesized by a high temperature solid state method, and the luminescence properties are investigated. Ba2Ca(BO3)2:Tb3+ can show an obvious green emission, and the peak locates at 551 nm, which corresponds to the 5D4→7F5 transition of Tb3+. Ba2Ca(BO3)2:Eu3+ can present the characteristic emission of Eu3+, and the peak locates at 600 nm, which is ascribed to the 5D0→7F2 transition of Eu3+. In order to achieve the emission-tunable phosphors, the Eu3+/Tb3+ co-doped Ba2Ca(BO3)2 are synthesized. When tuning the Eu3+ or Tb3+ concentration, Ba2Ca(BO3)2:Eu3+, Tb3+ can both show the tunable emission, which may be induced by the energy transfer from Tb3+ to Eu3+. 相似文献
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以Ba4Sm9.33Ti18O54微波介质陶瓷为基础,掺杂Lu2O3进行改性,形成固溶式为Ba4(Sm1-yLuy)9.33Ti18O54的结构.结果表明,掺杂Lu2O3能很好地把Ba4Sm9.33Ti18O544微波介质陶瓷的烧结温度降至1 260℃,当y=0.05时Ba4Sm9.33Ti18O54为类钨青铜结构,能得到介电性能较佳的微波介质陶瓷:4.33 GHz时εr约为76,Q·f约为2 532,τf为-42×10-6/℃;y<0.5时生成了类钨青铜结构晶相,y≥0.5主晶相变成烧绿石相,不具备介电性. 相似文献
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长余辉蓝色荧光粉SrSiO3:Eu2+,Dy3+的制备与发光性能研究 总被引:2,自引:2,他引:0
采用高温固相法,在碳粉还原条件下制备了SrSiO<,3>:Eu<'2+>,Dy<'3+>长余辉蓝光发光材料.研究了Eu<'2+>的掺杂浓度对样品发光性质的影响.用X射线衍射仪(XRD)、扫描电镜(SEM)和荧光光谱等手段对样品进行物相、形貌和光谱等性能的表征.研究结果表明,样品为单斜晶体,样品颗粒呈花束形;该荧光粉激发... 相似文献
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掺杂Sm_2O_3对BaSrTiO_3介电陶瓷性能的影响 总被引:1,自引:1,他引:0
以碳酸钡、碳酸锶和二氧化钛等为原料,Sm2O3为掺杂剂,制备了BaSrTiO3系介质陶瓷。利用SEM等仪器研究了陶瓷试样的微观形貌和介电性能。结果表明:当Sm2O3掺杂量低于0.10%摩尔分数时,Sm3+进入晶格A位;但随着Sm2O3掺杂量的增加,Sm3+越来越倾向于进入晶格B位。在Sm2O3掺杂量为摩尔分数0.10%时,BaSrTiO3陶瓷的相对介电常数达到最高值4800;随着Sm2O3掺杂量继续增加,陶瓷的介电损耗逐渐降低,最低降至0.0070。 相似文献
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采用水热法结合高温退火处理制备了YPO4:Ln3+(Ln=Eu,T b)荧光粉。通过X射线 粉末衍射(XRD)、扫描电镜(SEM)和荧光光谱(PL)对样品的结构、形貌和发光性能进行 表征。结果 表明:在水热条件下合成了含结晶水六角相结构的YPO4·0.8H2O :Eu3+和YPO4·0.8H2O:Tb3+前躯体;经过 800 ℃高温烧结2h后,前躯体 失去结晶水后得到球形、尺寸均一、表面光滑、四方锆石结构的YPO4:Eu3+和 YPO4:Tb3+荧光粉,颗粒平均粒径约为200 nm。在396 nm波长激发下,YPO4:Eu3+荧光粉可以获得Eu3+离 子的跃迁能级5D0→7FJ(J=1-4)特征发射,以磁偶极跃迁5D0→7F1(596 nm)的发光强度最强,观察到橙 红色发射,且Eu3+的最佳掺杂摩尔分数为11%。同时,YPO4: Tb3+荧光粉在372 nm的光激发下,在548 nm 处的5D4→7F5跃迁具有最高的荧光强度,观察到绿光发 射,且Tb3+最佳掺杂摩尔分数为7%。 相似文献
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以聚苯乙烯磺酸钠(PSSNa)为掺杂剂,三氯化铁(FeCl3)为氧化剂,通过化学氧化法制备了PEDOT/PSS复合物。利用傅里叶红外光谱表征了所制复合物的组成,通过循环伏安、交流阻抗及恒电流充放电测试研究了反应物摩尔比r(EDOT:PSS)对产物比容量的影响。实验结果表明适量添加PSS可以改善复合物的电容性能。在0.5 mol/L的Na2SO4水溶液中,纯PEDOT材料的比容量可达60 F/g,但其在快速充放电条件下有明显衰减,而摩尔比r(EDOT:PSS)=1:0.5时制备的复合材料比容量则能保持较好的稳定性。当摩尔比r(EDOT:PSS)增大至1:2时所得复合物电容性能下降。 相似文献
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采用传统电子陶瓷工艺合成了Ca-B-Si(CBS)玻璃掺杂的Ba(Mgl/3Nb2/3)O3微波介质陶瓷,研究了CBS掺杂量对陶瓷微波介电性能的影响。结果表明:CBS掺杂可促进陶瓷烧结并提高B位1:2有序度,进而降低微波介质损耗。当w(CBS)=3%时,陶瓷烧结温度由纯相时的1 500℃以上降至1 250℃,表观密度提高到6.32 g/cm3以上,陶瓷的微波介电性能达到最佳值:εr=26,Q.f=67 800 GHz(8 GHz),τf=25×10–6/℃。该陶瓷有望成为用于高频段微波器件的材料。 相似文献
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Eu3+ and Sm3+ co-doped SrMoO4 phosphors have been successfully prepared via a simple surfactant-free hydrothermal method. The as-prepared phosphors present dumbbell-like agglomerates and comprise of many nanoparticles of 150–300 nm in diameter. Eu3+ and Sm3+ co-doped SrMoO4 phosphors display all the characteristic excitations and emissions of Eu3+ and Sm3+. The introduction of Sm3+ can generate a strong excitation line at 403 nm, originating from the 6H5/2 → 4K11/2 transition of Sm3+, which significantly broadened the excitation region for matching the near ultraviolet light emitting diodes (~400 nm). And Sm3+ ions can transfer the absorbed energy to Eu3+ ions efficiently, so the intensity of the main emission peak at 614 nm due to 5D0 → 7F2 transition of Eu3+ are strengthened by the co-doping of Sm3+. The doping concentration of Eu3+/Sm3+ was optimized. In addition, the possible energy transfer mechanism has been investigated and is discussed in detail. 相似文献