首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
采用溶胶-凝胶法合成了以Sr2MgSi2O7为基质,掺杂Eu^2 ,Dy^3 的长余辉发光材料,并表征其结构,激发-发射光谱和余辉衰减曲线。XRD分析表明,所合成的样品为Sr2MgSi2O7晶体结构。发光粉体的激发波长范围较宽,表明从紫外至可见光均可激发该发光材料。发射光谱主峰位于466nm。样品在自然光照射后持续发出明亮的蓝光,余辉时间持续8h以上。  相似文献   

2.
溶胶-凝胶法制备Sr_2MgSi_2O_7∶Eu~(2+),Dy~(3+)长余辉发光材料   总被引:1,自引:1,他引:0  
采用溶胶-凝胶法合成了以SrMgSi2O7为基质,掺杂Eu2+,Dy3+的长余辉发光材料,并表征其结构,激发-发射光谱和余辉衰减曲线。XRD分析表明,所合成的样品为SrMgSi2O7晶体结构。发光粉体的激发波长范围较宽,表明从紫外至可见光均可激发该发光材料。发射光谱主峰位于466nm。样品在自然光照射后持续发出明亮的蓝光,余辉时间持续8h以上。  相似文献   

3.
采用溶胶-凝胶法合成了以Sr2MgSi2O7为基质,掺杂Eu^2 ,Dy^3 的长余辉发光材料,并表征其结构,激发-发射光谱和余辉衰减曲线。XRD分析表明,所合成的样品为Sr2MgSi2O7晶体结构。发光粉体的激发波长范围较宽,表明从紫外至可见光均可激发该发光材料。发射光谱主峰位于466nm。样品在自然光照射后持续发出明亮的蓝光,余辉时间持续8h以上。  相似文献   

4.
长余辉材料Sr2MgSi2O7:Eu2+,Dy3+的制备及发光性能研究   总被引:1,自引:0,他引:1  
在碳粉还原条件下,采用高温固相法制备出了亮度高、余辉时间长的Sr2MgSi2O7Eu2+,Dy3+长余辉发光材料,并对其性能以及影响其发光性能的因素进行了研究.发光粉体还原后的发射光谱表明,其主发射峰位于463 nm左右;余辉衰减曲线证明其余辉衰减过程存在快速衰减和慢衰减两个过程.  相似文献   

5.
采用微乳液法合成了MAl2O4:Eu^2+,Dy^3+(M=Ca,Sr,Ba)长余辉发光材料,并对其晶体结构和发光性能进行了比较与讨论。XRD分析表明,所合成的Ca2O4:Eu^2+,Dy^3+,SrAl2O4:Eu^2+,Dy^3+粉体为单斜晶系结构,BaAl2O4:Eu^2+,Dy^3+粉体为六方晶体结构。MAl2O4:Eu^2+,Dy^3+(M=Ca,Sr,Ba)发光材料的激发光谱都为一宽带连续谱,表明从紫外至可见光均可有效的激发该材料。发射光谱的发射波长峰值分别为440nm(M=Ca),520nm(M=Sr)和496nm(M=Ba)。对应的发光颜色分别为蓝色、黄绿色和蓝紫色。余辉衰减曲线分为快衰减、中间过渡衰减和随后极长的慢衰减过程,符合双曲线方程I=At^-n,余辉亮度与时间顺序为Sr〉Ca〉Ba。  相似文献   

6.
利用高温固相法合成了Zn2GeO4:Mn2+以及Zn2GeO4:Mn2+,Yb3+绿色发射长余辉发光材料,对样品进行了X射线衍射分析、荧光光谱分析、色坐标、热释发光以及发光寿命测量.分析结果表明,在1050℃下烧结3h的Zn2CeO4为单相产物,所得Zn2GeO4:Mn2+发光材料具有良好的发光性能,在紫外灯激发下发出最强发射位于528 nm的宽带发射并具有优良的长余辉发光特性,其色坐标值分别为x=0.145,y=0.773.Yb3+共掺杂对其长余辉发光性能提高明显.余辉发光在暗场环境下肉眼可观察的持续时间超过2h.通过热释光谱对陷阱进行了分析.对Yb3+共掺杂的长余辉发光增强机理进行了讨论.  相似文献   

7.
稀土超长余辉材料及其涂料的研究   总被引:10,自引:1,他引:9  
以碳酸锶、氧化铝、氧化铕和氧化镝为原料,用高温固相反应法合成了稀土超长余辉发光材料SrAl2O4:Eu^2 ,Dy^3 。测试了该发光材料的激发光谱、发射光谱、余辉亮度及余辉时间,激发光谱主峰分别位于320和360nm处,激发波长的范围较宽,从紫外到可见光区均可激发该发光材料。发射光谱的主峰位于520nm,发光颜色为黄绿色,余辉可达16h以上。解释了超长余辉发光材料的发光机制。以苯丙乳液为成膜物,添加适量的发光粉及适当的助剂研制出一种超长余辉发光涂料。确定出了该涂料的最佳配方,测定了涂料的各种性能,并对影响涂料性能的主要因素进行了探讨。  相似文献   

8.
利用高温固相法合成了Ca2nO4:Eu3+色发射长余辉发光材料,对样品进行了X射线衍射分析、荧光光谱分析、形貌分析以及发光寿命测量.分析结果表明,在1350℃下烧结3 h的Ca2SnO4:Eu3+为单相产物,所得Ca2SnO4:Eu3+发光材料具有良好的发光性能,在267 nm紫外线激发下发出最强发射位于617 nm的锐线发射,并且具有明显的长余辉发光性能.  相似文献   

9.
孙中新 《无机化学学报》2012,28(6):1229-1233
利用高温固相法合成了Zn2GeO4∶Mn2+以及Zn2GeO4∶Mn2+,Yb3+绿色发射长余辉发光材料,对样品进行了X射线衍射分析、荧光光谱分析、色坐标、热释发光以及发光寿命测量。分析结果表明,在1 050℃下烧结3 h的Zn2GeO4为单相产物,所得Zn2GeO4∶Mn2+发光材料具有良好的发光性能,在紫外灯激发下发出最强发射位于528 nm的宽带发射并具有优良的长余辉发光特性,其色坐标值分别为x=0.145,y=0.773。Yb3+共掺杂对其长余辉发光性能提高明显。余辉发光在暗场环境下肉眼可观察的持续时间超过2 h。通过热释光谱对陷阱进行了分析。对Yb3+共掺杂的长余辉发光增强机理进行了讨论。  相似文献   

10.
通过高温固相法在空气条件下制得cd2Ge7016:Pr3’长余辉发光材料。测其结构为一单相。分析了cd2Ge70…cd2Ge7016:Pr3’的激发光谱和发射光谱,指出Cd2Ge7016:Pr3’的发光是Cd2Ge7016本身和Pr3’离子发射产生,基质的发光是Cd2Ge70.6中有陷阱能级,电子从导带跃迁到陷阱能级而产生,Pr3’的发光是该离子的4f一4f跃迁产生的;并把该材料的长余辉性质归结为基质结构中有电子陷阱和空穴陷阱,电子陷阱和空穴陷阱分别能储存电子和空穴,从而产生余辉。并提出余辉机理模型。  相似文献   

11.
Scandium magnesium gallide, Sc2MgGa2, and yttrium magnesium gallide, Y2MgGa2, were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo2FeB2‐type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc2MgGa2 was determined from single‐crystal diffraction intensities and the isostructural Y2MgGa2 was identified from powder diffraction data.  相似文献   

12.
13.
On Dialkali Metal Dichalcogenides β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 and Rb2Te2 The first presentation of pure samples of α- and β-Rb2S2, α- and β-K2Te2, and Rb2Te2 is described. Using single crystals of K2S2 and K2Se2, received by ammonothermal synthesis, the structure of the Na2O2 type and by using single crystals of β-Na2S2 and β-K2Te2 the Li2O2 type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na2O2 type to the Li2O2 type will be explained by means of the examples α-/β-Na2S2 and α-/β-K2Te2. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb2S2 is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence.  相似文献   

14.
15.
[(n‐Bu)2Sn(O2PPh2)2] ( 1 ), and [Ph2Sn(O2PPh2)2] ( 2 ) have been synthesized by the reactions of R2SnCl2 (R=n‐Bu, Ph) with HO2PPh2 in Methanol. From the reaction of Ph2SnCl2 with diphenylphosphinic acid a third product [PhClSn(O2PPh2)OMe]2 ( 3 ) could be isolated. X‐ray diffraction studies show 1 to crystallize in the monoclinic space group P21/c with a = 1303.7(1) pm, b = 2286.9(2) pm, c = 1063.1(1) pm, β = 94.383(6)°, and Z = 4. 2 crystallizes triclinic in the space group , the cell parameters being a = 1293.2(2) pm, b = 1478.5(4) pm, c = 1507.2(3) pm, α = 98.86(3)°, β = 109.63(2)°, γ = 114.88(2)°, and Z = 2. Both compounds form arrays of eight‐membered rings (SnOPO)2 linked at the tin atoms to form chains of infinite length. The dimer 3 consists of a like ring, in which the tin atoms are bridged by methoxo groups. It crystallizes triclinic in space group with a = 946.4(1) pm, b = 963.7(1) pm, c = 1174.2(1) pm, α = 82.495(6)°, β = 66.451(6)°, γ = 74.922(6)°, and Z = 1 for the dimer. The Raman spectra of 2 and 3 are given and discussed.  相似文献   

16.
17.
The structures of the hypophosphites KH2PO2 (potassium hypophosphite), RbH2PO2 (rubidium hypophosphite) and CsH2PO2 (caesium hypophosphite) have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of alkali cations and hypophosphite anions, with the latter bridging four cations within the same layer. The Rb and Cs hypophosphites are isomorphous.  相似文献   

18.
Summary The ability of [MoS4]2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe2+. The present study has been restricted to linear complexes such as (NEt4)2 [Cl2FeS2MoS2] and (NEt4)2[Cl2FeS2MoS2FeCl2]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS2, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl2]2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl4Fe2MoS4]2–[Cl2FeMoS4]2–+FeCl2. The equilibrium constant, KD, was evaluated by differential pulse polarography. KD is tightly related to the donor number of the solvent.  相似文献   

19.
TG and DTA studies on Me3SnO2PCl2, Me2Sn(O2PCl2)2 and Ph3SnO2PCl2 were carried out under dynamic argon atmosphere. The results show that the decomposition proceeds in different stages leading to the formation of Sn3(PO4)2 as a stable product. This compound was characterized by IR spectroscopy. Decomposition schemes involving reductive elimination reactions were proposed.  相似文献   

20.
Wu YT  Linden A  Siegel JS 《Organic letters》2005,7(20):4353-4355
[reaction: see text] Fluoranthene 2 and heptacycle 3 are easily accessible from the reaction of diyne 1 and norbornadiene (NBD) in the presence of the rhodium catalyst. The unusual [(2+2)+(2+2)] adduct 3 was confirmed by the X-ray crystal structure analysis.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号