TiO2-SiO2∶Eu3+荧光粉的制备及发光性能的研究

采用溶胶凝胶法制备TiO₂-SiO₂∶Eu³⁺发光材料，通过XRD, FTIR,荧光光谱仪的测试表征材料的结构和发光性能。结果表明，通过溶胶凝胶法成功的制备了TiO₂-SiO₂复合氧化物荧光粉。FTIR证明1070cm^-1为Si-O-Si的反对称伸缩振动，795cm^-1为Si-O-Si的对称伸缩振动，937cm^-1为Ti-O-Si特征峰。荧光光谱表明以465nm为激发波长，Eu³⁺在612nm(⁵D₀→⁷F₂)红色发光最强。Ti/Si为1∶1时，Eu³⁺掺杂浓度为4mol%时发光强度最佳。     

Ba2+、MoO42-掺杂对NaCaPO4：Eu3+荧光粉发光性能的影响研究

为提高红色荧光粉的发光强度和色纯度,以硝酸钙、硝酸钠、硝酸铕、磷酸二氢铵、钼酸铵、硝酸钡为原料,采用高温固相法合成了NaCa_1-xPO₄：xEu³⁺、NaCa_1-x（PO₄）_1-y（MoO₄）_y：xEu³⁺、NaCa_1-x-zPO₄：xEu³⁺,zBa²⁺系列红色荧光粉。探讨了Eu³⁺单掺杂和Eu³⁺/MoO₄^2-、Eu³⁺/Ba²⁺共掺杂对荧光粉发光性能的影响。用X射线衍射（XRD）、荧光分光光度计、色坐标等对荧光粉的结构进行表征。研究结果表明：掺杂Eu³⁺、MoO₄^2-、Ba²⁺后NaCaPO₄晶系没有发生变化,但是晶胞参数发生了变化,说明Eu³⁺、MoO₄^2-、Ba²⁺进入NaCaPO₄晶格中。在393 nm紫外光激发下,荧光粉发射光谱图出现两个Eu³⁺比较强的特征发射峰,分别属于Eu³⁺的⁵D₀→⁷F₁和⁵D₀→⁷F₂跃迁。与单掺杂16%Eu³⁺荧光粉相比,共掺杂16%Eu³⁺/3%MoO₄^2-或16%Eu³⁺/6%Ba²⁺荧光粉的发射光谱中⁵D₀→⁷F₂跃迁产生的发射峰强度均高于单掺杂16%Eu³⁺荧光粉的发射峰强度,其⁵D₀→⁷F₂与⁵D₀→⁷F₁发射光强度之比（R）分别为1.76（R_Mo）和1.28（R_Ba）,都大于单掺杂16%Eu³⁺荧光粉的R_Eu（0.99）,共掺杂Eu³⁺/MoO₄^2-荧光粉的色纯度比单掺杂Eu³⁺和共掺杂Eu³⁺/Ba²⁺荧光粉的色纯度更好。     

锡掺杂溴铅铯钙钛矿纳米晶的合成、结构及发光性能

为了降低CsPbBr₃钙钛矿纳米晶的Pb²⁺毒性，同时优化Sn²⁺掺杂CsPbBr₃纳米晶的发光性能，采用热注入法合成了Sn²⁺掺杂的Cs Pb_1-xSn_x Br₃纳米晶(x=0.1、0.2、0.3、0.4和0.5)，使用X射线衍射仪(XRD)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)和荧光光谱仪(PL)对所合成纳米晶的物相结构、微观形貌及发光性能进行表征。结果表明，纳米晶中掺杂的Sn元素以Sn²⁺和Sn⁴⁺形式存在，且含有Pb²⁺阳离子空位，当x=0.3时，Sn元素实际掺杂物质的量分数高达43.91%。x=0.1～0.4时，纳米晶为纯单斜相钙钛矿结构，尺寸约16～20 nm，立方块形貌较均匀。Sn²⁺掺杂调控了Cs Pb_1-xSn_x Br₃纳米晶的...     

掺铕钼酸钆发光材料的制备及性质研究

以氧化钆(Gd₂O₃)、氧化铕(Eu₂O₃)、钼酸铵(H₈Mo N₂O₄)、柠檬酸(C₆H₈O₇)为原料,采用超声波辅助溶胶-凝胶法成功制备了Gd₂(Mo O₄)₃:Eu³⁺荧光粉发光材料。讨论了Eu离子掺杂浓度和前驱体是否煅烧对荧光材料性能的影响,利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)、荧光光谱仪(LS)对材料进行表征和分析。结果表明：在403 nm最优激发波长激发下,材料的发射峰位于470～530nm之间,Eu离子掺杂浓度及是否煅烧都会对材料的形貌和发光性能产生影响。     

NaYF4∶Yb3+,Tm3+稀土掺杂上转换纳米材料的制备与条件优化

利用溶剂热法制备油相NaYF₄∶Yb³⁺,Tm³⁺,经“超声去油”后得到水相NaYF₄∶Yb³⁺,Tm³⁺,并对稀土离子掺杂比例、反应温度、反应时间和油酸体积分数进行条件优化，通过X-射线衍射(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)和分子荧光光谱仪(MFS)对其进行表征。结果表明，当稀土离子掺杂比例为NaYF₄∶25%Yb³⁺,0.3%Tm³⁺,反应时间为60 min,反应温度为300℃,油酸体积分数为20.6%时，合成的水相NaYF₄∶Yb³⁺,Tm³⁺为六方晶型结构，六边形两平面间的平均粒径大小约为50 nm,形貌均匀、尺寸均一、分散性良好，980 nm近红外光激发下，在452和478 nm处荧光强度最大，且发出明亮的蓝色荧光。水相NaYF₄∶Yb³⁺,Tm...     

稀土Eu3+掺杂对SnO2薄膜光学和电学性质的影响

基于旋涂法制备了Eu³⁺掺杂的SnO₂薄膜，并通过紫外-可见分光光度计(UV-Vis)、电流-电压测试和原子力显微镜(AFM)等对样品的光学性质、电学性质和表面形貌进行了表征。研究发现，在200nm～380nm的波长范围内，掺杂15at%Eu³⁺的SnO₂薄膜光吸收率最高；在380nm～700nm的可见光范围内，掺杂15at%Eu³⁺的SnO₂薄膜光透射率较强，掺杂20at%Eu³⁺的SnO₂薄膜光吸收率最强。随着Eu³⁺掺杂浓度的增加，SnO₂薄膜的电阻增加，表面的平均粗糙度显著降低。     

白光SrMoO4:Eu3+,K+@g-C3N4荧光粉的合成及其性能研究

为了获得单一基质白光荧光粉，以三聚氰胺为原料，采用热分解法制备g-C₃N₄蓝色荧光粉，采用高温固相法制备了Sr_0.92Mo O₄:0.08Eu³⁺(SMO:E)和Sr_0.82Mo O₄:0.08Eu³⁺,0.10K⁺(SMO:EK)红色荧光粉，通过沉淀吸附反应制备了Sr_0.82Mo O₄:0.08Eu³⁺,0.10K⁺@0.013g-C₃N₄(SMO:EK-CN)复合荧光粉。利用X射线粉末衍射、红外光谱、荧光光谱、热猝灭分析对荧光粉进行表征，分别探讨了Eu³⁺单掺杂和Eu³⁺、K⁺共掺杂以及Eu³⁺、K⁺、g-C₃N₄     

Eu3+掺杂Ba2LaZrO5.5基荧光粉的制备及发光研究

以溶胶凝胶法制备了Ba₂LaZrO_5.5:Eu³⁺荧光粉，探讨溶液的pH值、焙烧温度和掺杂Eu³⁺的量对荧光粉的结构和发光的影响。证实了当pH=3、焙烧温度为800℃时Ba₂LaZrO_5.5:21%Eu³⁺荧光粉为立方体钙钛矿结构；在280nm激发下基质Ba₂LaZrO_5.5在468nm处有较强的蓝光发射，而Ba2LaZrO_5.5:21%Eu³⁺荧光粉在612nm处有Eu³⁺的红光发射峰最强。     

Ce3+–Eu3+共掺Y3Al5O12透明陶瓷荧光性能

Y₃Al₅O₁₂:Ce³⁺(YAG:Ce³⁺)发射谱中红光成分的不足导致了白光LED色温偏高且显色性较差,一种解决方案是引入能发射红光的激活离子与Ce³⁺共掺杂以使YAG:Ce³⁺发射谱红移。本工作报道了Ce³⁺–Eu³⁺共掺Y₃Al₅O₁₂(YAG:Ce³⁺/Eu³⁺)透明陶瓷的制备、结构和荧光性能。该材料体系在Eu含量高达25%时仍保持纯石榴石相结构,且Eu³⁺的荧光猝灭浓度高达9%左右,比Pr³⁺和Sm³⁺等离子更适合用作YAG的红光发射激活剂。YAG:Ce³⁺/Eu³⁺透明陶瓷在蓝光(如442和466 nm)激发下的Ce³⁺荧光发射随着Eu含量的...     

类蓝宝石立方氧化铝透明陶瓷的冷高压制备、显微结构和光学性能

采用GPa级高压低温烧结制备出立方γ-氧化铝(γ-Al₂O₃)透明陶瓷材料,通过调节温度并研究了立方γ-氧化铝陶瓷在常压和高压下的相变行为、显微结构和掺杂稀土离子(Eu³⁺)的发光特性。结果表明：采用5 GPa压力和温度为300℃所烧结的立方氧化铝透明陶瓷,其直线透过率在可见光和近红外波段达到86%,与蓝宝石单晶体在该波段的透光性能一致,并且其平均晶粒尺寸小于20 nm,Vickers硬度达16 GPa。另外,在立方氧化铝基质中掺入三价稀土Eu³⁺后,三价Eu³⁺能自还原为二价Eu²⁺。当对Eu³⁺掺杂γ-Al₂O₃材料加热至300℃后,其荧光光谱表现出最强的Eu²⁺发射,继续升高温度至1 200℃后,二价Eu²⁺的发射强度降低至最小值,并恢复为三价Eu³⁺的发射。这表明立方氧化铝具有自还原的结构优势,有利于获得低价金属离子掺...     

白光LED用红色荧光粉Gd2-xMo3O9:Eux3+制备和研究

用高温固相法成功制备了Gd2-xMo3O9:Eux3+,用XRD荧光光谱仪对其物相以及粉体的激发和发射光谱进行表征和研究;结果表明:在395和464nm两主激发峰均可得到616nm处红光发射峰,属于Eu3+典型的5D0→7F2的跃迁所致。由464nm激发得到的发射峰为单峰,峰宽较窄且发射强度较强。     

Eu3+,Ce3+共掺硼硅酸锌玻璃的发光性能及能量传递

采用高温液相法制备了50ZnO-30SiO2-20B2O3∶Eu3+,Ce3+玻璃。测试了样品的激发光谱和发射光谱。结果表明:在紫外光激发下,该玻璃可以发出明亮的红色光。其中580 nm,593 nm,617 nm,655 nm和706 nm波长处的发射峰分别对应于Eu3+的5D0→7F0,5D0→7F1,5D0→7F2,5D0→7F3和5D0→7F4跃迁发射,其中5D0→7F2跃迁发射强度最大,同时发现在450 nm处存在Ce3+的5D→2FJ(J=7/2,5/2)特征发射峰。首次发现在该发光玻璃50ZnO-30SiO2-20B2O3∶Eu3+,Ce3+中存在着Ce3+→Eu3+能量传递现象,其中Ce3+起敏化作用。     

Plasma-electrochemical synthesis of europium doped cerium oxide nanoparticles

In the present study,a plasma-electrochemical method was demonstrated for the synthesis of europium doped ceria nanoparticles.Ce(NO3)3· 6H2O and Eu(NO3)3·5H2O were used as the starting materials and being dissolved in the distilled water as the electrolyte solution.The plasma-liquid interaction process was in-situ investigated by an optical emission spectroscopy,and the obtained products were characterized by complementary analytical methods.Results showed that crystalline cubic CeO2:Eu3+ nanoparticles were successfully obtained,with a particle size in the range from 30 to 60 nm.The crystal structure didn't change during the calcination at a temperature from 400℃ to 1000℃,with the average erystallite size being estimated to be 52 nm at 1000℃.Eu3+ ions were shown to be effectively and uniformly doped into the CeO2 lattices.As a result,the obtained nanophosphors emit apparent red color under the UV irradiation,which can be easily observed by naked eye.The photoluminescence spectrum further proves the downshift behavior of the obtained products,where characteristic 5Do → 7F1,2,3 transitions of Eu3+ ions had been detected.Due to the simple,flexible and environmental friendly process,this plasma-electrochemical method should have great potential for the synthesis of a series of nanophosphors,especially for bio-application purpose.     

Li+掺杂浓度对Sr3ZnNb2O9:Eu3+荧光粉发光特性的影响

Li⁺作为电荷补偿剂可以提高Sr₃ZnNb₂O₉:Eu³⁺荧光粉的发光强度和热稳定性。本文通过高温固相反应成功制备了Sr₃ZnNb₂O₉:xEu³⁺,yLi⁺(0≤x≤0.5,0≤y≤0.5)荧光粉,为了鉴定和描述样品的物相、发光特性和热稳定性,进行了XRD和发光光谱测试。结果表明:Eu³⁺和Li⁺已经成功掺入到基质材料中,并取代Zn²⁺位点;Li⁺的最佳掺杂浓度为0.3(摩尔分数),浓度猝灭类型是在最近邻离子之间;掺杂Li⁺提高了荧光粉的热稳定性,活化能为0.193 eV,CIE色坐标为(0.651,0.349),非常接近国际照明委员会规定的标准色坐标。     

Effect of codoping LiNbo3:Eu3 crystal with Mg2 ions on the Eu3 optical absorption spectrum

In this work the optical absorption spectra of Eu³⁺ doped LiNbO₃ measured as a function of Li/Nb ratio are presented. Two Eu³⁺ sites, dealing with the Nb⁺⁵ and Li⁺ lattice sites, have been characterized by their corresponding ⁷F_o -⁵D₂ optical transitions. A doubly doped sample (LiNbo³: Mg, Eu) has been used to study the influence of Mg²⁺ ions on the Eu³⁺ optical absorption spectrum. The main effect is a shifting of the relative occupation of the two Eu³⁺ sites.     

镝(Ⅲ)-BDPPPD配合物的合成及其荧光性质

以二氧六环为溶剂 ,在 pH约为 7的条件下 ,分别以n (Dy3+ )∶n (BDPPPD) =2∶3和n (Dy3+ )∶n(BDPPPD)∶n(Phen ) =2∶3∶2的量比 (Phen为邻菲罗啉 ) ,合成了Dy(Ⅲ)的 1,5 双 (1′,3′ 二苯基 5′ 氧代吡唑 4′ 基 ) 1,5 戊二酮 (BDPPPD)的二元配合物Dy2 (BDPPPD) 3·6H2 O和三元配合物Dy2(BDPPPD) 3(Phen) 2 ·2H2 O ,收率为 91 2 %和 89 6 %。通过化学分析、元素分析和热分析确定了配合物的组成 ,通过FT -IR谱对配合物进行了表征。测定了配合物的荧光光谱 ,配合物的荧光发射峰位于 481和 5 76nm附近 ,分别相应于Dy3+ 的 4 F9/2 → 6H15/2 和 4 F9/2 → 6H13/2 跃迁 ,说明配合物发射Dy(Ⅲ)的特征荧光。第二配体Phen具有荧光增强作用 ,三元配合物Dy2 (BDPPPD) 3(Phen) 2 ·2H2 O最大发射峰 (5 76nm)的荧光强度是二元配合物Dy2 (BDPPPD) 3·6H2 O的 1 6 8倍。配合物具有较强荧光 ,说明BDPPPD的三重态能级与Dy3+ 最低激发态 (4 F9/2 )能级具有良好匹配 ,且其吸光系数较高 ,BDPPPD是Dy(Ⅲ)发光配合物的适宜配体     

Fluorescence spectra of Eu3 , Tb3 , Dy3 and Ho3 doped certain powder phosphors

This paper reports the photoluminescence spectral properties of Eu³⁺, Tb³⁺, Dy³⁺ and Ho³⁺ doped LaOX, YOX, (La, Gd)OX, and (La, Y)OX (X=F, Cl) powder phosphors. Under the UV-light these phosphors have exhibited bright reddish-orange, green, yellowish-blue and bluish-green colours. This papers also describes the effects of the halides change in the host material chosen specifically.     

Luminescent properties of Eu-doped YTaO4 powders

YTaO₄:Eu³⁺ powders were synthesized by a flux method with LiCl. The use of a flux in the synthesis of M′–YTaO₄ facilitated the reaction of raw materials, leading to lowering the heating temperature, but not effective at the high firing temperature. The red emission peaks were observed around 613 nm with an excitation wavelength of 254 nm. Emission peaks were composed of two sets around 613 nm and 590 nm, which originated from ⁵D₀–⁷F₂ and ⁵D₀–⁷F₁, respectively. PL intensity of YTaO₄:Eu³⁺ prepared with a small amount of LiCl (10 wt%) significantly depended on the firing temperatures, while that with a larger amount of LiCl (40 wt%) slightly relied on firing temperatures. The highest PL intensity could be obtained at the firing conditions of 1300 °C and 10 wt% LiCl.     

High-gravity-assisted green synthesis of rare-earth doped calcium molybdate colloidal nanophosphors

In this work, we report an innovative route for the synthesis of rare-earth doped calcium molybdate (CaMoO₄) nanophosphors by using high gravity rotating packed bed (RPB) technology and paraffin liquid as the solvent. The significant intensified mass transfer and micromixing of reactants in the RPB reactor are benefiting for homogeneous doping of rare-earth ions in the host materials, leading to nanophosphors with high quantum efficiency. The use of liquid paraffin as the solvent eliminates the safety risks associated with volatile organic compounds, increasing the potential for clean production of nanophosphors. Under excitation of deep ultraviolet (DUV) light, the CaMoO₄:Na⁺, Eu³⁺ nanophosphors exhibit red emission at peak wavelength of 615 nm and quantum yield of up to 35.01%. The CaMoO₄:Na⁺,Tb³⁺ nanophosphors exhibit green emission at peak wavelength of 543 nm with quantum yield of up to 30.66%. The morphologies of the nanophosphors are tunable from nanofibers through nanorods to nanodots and the possible mechanism of controlling the formation of different nanostructures is proposed on the basis of experimental results and theoretical analysis of mesoscience. These nanophosphors are highly dispersible in organic solvents and utilized for fabricating fabrication of flexible, freestanding luminescent films based on silicone resin. We also demonstrate the red LEDs consisting of the hybrid films of CaMoO₄:Na⁺,Eu³⁺ nanoparticles as color-converting phosphors and DUV LEDs as illuminators, offering strong potential for future nanophosphors-basedsolid-state lighting systems.