稀土微孔晶体材料的高温高压合成及荧光性质的研究
发布时间：2018-08-06 14:14
【摘要】：稀土因其优良的光学、电学、磁学等物理性质，已被广泛的应用于生活中的各个方面。作为一种传统材料，硅酸盐的合成和应用研究一直是科研工作者研究的热点。而作为硅酸盐材料的新秀，具有规则孔道结构的硅酸盐化合物在近几十年的研究中也表现出许多优异的性质，并在催化、吸附等方面表现出巨大的应用潜力。将稀土元素独特的发光性质与微孔硅酸盐均一的孔道性质有机的结合在一起，一直是人们感兴趣并不断探索的研究课题。微孔稀土硅酸盐的合成大多都是采用中温水热法在200°C以下的温度条件下合成的，反应容器为不锈钢反应釜。本论文通过Quickpress3.0活塞-圆筒式高压反应装置和HR-1B-2型LECO高温高压水热反应装置，尝试在更高的压力和温度条件下，对具有新颖结构的微孔稀土硅酸盐/锗酸盐化合物的合成进行研究。在0.5~1GPa压力范围，300~700°C温度范围内成功合成出了一系列结构新颖的稀土硅酸盐及锗酸盐化合物，并对它们的晶体结构和荧光性质进行了研究。 （1）采用高温高压合成方法，，成功合成出了一个新的Na15Eu3Si12O36单晶。通过单晶X射线衍射分析对其晶体结构进行了解析，并且用粉末X射线衍射和X射线能谱分析对单晶解析的结果进行了验证。单晶结构解析的结果表明，该晶体是由[Si6O12]n12n-环硅酸盐阴离子和EuO6八面体通过共用顶端O原子而相互连接所构筑成的三维开放骨架结构。该结构含有由EuO6八面体和SiO4四面体共同限定组成的沿[010]方向的6元环孔道结构。同时，单晶解析的结果表明，在其结构中Na(2)+和Na(3)+离子的位置分别被Eu(2)和Eu(3)部分占据，这种按统计无序的Eu/Na占有率无序对Na15Eu3Si12O36的荧光性质有着重要的影响，而这一结果在对其荧光性质测试中被验证。 （2）在高温高压条件下，成功合成出了具有新结构的铕硅酸盐，其化学构成为Na3EuSi6O15·1.47H2O。单晶X射线衍射晶体结构解析的结果表明，该晶体是由波浪形SiO4四面体单层之间通过EuO7多面体相互连接起来而形成的三维开放骨架结构。SiO4四面体所形成的单层沿[010]轴方向具有4，5，6，8元环孔道结构。Na3EuSi6O15·1.47H2O的三维骨架结构中存在着由EuO7多面体和SiO4四面体限定形成的沿[100]方向的4，8元环孔道结构，以及沿[001]方向的5，6元环孔道结构。对其热稳定性和荧光性质的研究表明，它的结构在800°C依然可以稳定存在，并且表现出红光发射。这些结果证明Na3EuSi6O15·1.47H2O是一种具有良好热稳定性的荧光材料。 （3）采用高温高压熔盐法，以KF·2H2O和KOH作为助熔剂，成功合成出了一个具有新结构的含氟微孔铕硅酸盐，其化学构成为K2EuSi4O10F。通过单晶X射线衍射、粉末X射线衍射分析确定了其晶体结构。K2EuSi4O10F的结构是由SiO4四面体所构成的沿b轴方向的管状链，以及沿b轴方向排列的EuO4F2八面体无限链之间通过共用顶端的氧原子而相互连接形成的沿b轴方向具有6，8元环孔道结构的三维开放骨架结构。对其荧光性质的研究表明，K2EuSi4O10F晶体具有强烈的红光发射，是一种具有潜在应用价值的红光荧光材料。 （4）采用HR-1B-2型LECO高温高压水热反应装置，成功合成出了一系列具有2D层状结构的稀土锗酸盐：K3[LnGe3O8(OH)2]。通过单晶X射线衍射、粉末X射线衍射、EDS、红外光谱对其结构进行了研究。单晶结构分析表明K3[LnGe3O8(OH)2]是由[GdGe3O8(OH)2]n3n阴离子骨架所构成的二维层状结构，其基本结构由GeO4/GeO4H四面体和GdO6八面体通过桥氧相互连接而形成的平行于（010）晶面方向的GdGe3O8(OH)2单层，而单层之间则由O H···O键相互连接形成沿b轴方向按[ABAB…]顺序排列。对共掺杂样品K3[Gd1-xTbxGe3O8(OH)2]（x=0.1，0.3）荧光性质的研究表明，在其荧光光谱中存在着Gd3+和Tb3+的能量传递过程，荧光发射光谱表现出Tb3+离子的特征发射，是一种潜在的绿色荧光材料
[Abstract]:Rare earth has been widely used in all aspects of life because of its excellent optical, electrical, magnetic and other physical properties. As a traditional material, the research of the synthesis and application of silicate has always been a hot spot for researchers. As a new show of silicate materials, the silicate compounds with regular pore structure have been used in recent decades. Many excellent properties have also been shown in the study, and great potential applications have been shown in catalysis and adsorption. It is a research subject that people are interested in and continuously explore the unique luminescence properties of rare earth elements and microporous silicate homogeneous pore properties. The medium temperature hydrothermal method was synthesized under the temperature of less than 200 C. The reaction vessel was a stainless steel reaction kettle. In this paper, the Quickpress3.0 piston cylindrical high pressure reactor and the HR-1B-2 LECO high temperature and high pressure hydrothermal reaction device were used to try the microporous rare earth silicate with new structure under higher pressure and temperature. The synthesis of germanate compounds was studied. A series of novel rare earth silicates and germanate compounds were successfully synthesized in the range of 0.5~1GPa pressure and 300~700 C temperature range, and their crystal structure and fluorescence properties were studied.
(1) a new Na15Eu3Si12O36 single crystal was successfully synthesized by high temperature and high pressure synthesis. The crystal structure of the single crystal was analyzed by X ray diffraction analysis of single crystal. The results of the single crystal analysis were verified by powder X ray diffraction and X ray energy spectrum analysis. The crystal structure analysis showed that the crystal was composed of [Si6O12]n1 A three-dimensional open framework constructed by the 2n- ring silicate anions and the EuO6 eight sides by sharing the apical O atoms. The structure contains a 6 membered ring channel structure along [010] direction composed of EuO6 eight and SiO4 tetrahedron. The results of single crystal analysis show that Na (2) + and Na (3) + ions are in its structure. The positions were occupied by Eu (2) and Eu (3), and the statistical disordered Eu/Na occupancy disorder had an important effect on the fluorescence properties of Na15Eu3Si12O36, and this result was verified in the test of its fluorescence properties.
(2) the new structure of europium silicate is successfully synthesized at high temperature and high pressure. The chemical composition of the Na3EuSi6O15. 1.47H2O. single crystal X ray diffraction crystal structure analysis shows that the crystal is a three dimensional open skeleton structure.SiO4 four formed by the interaction of EuO7 polyhedron between the wavy SiO4 tetrahedron monolayers. The structure of the 4,8 element ring along the [100] direction, formed by the EuO7 polyhedron and SiO4 tetrahedron, and the 5,6 element ring path along the [001] direction in the three-dimensional skeleton structure of the 4,5,6,8 element ring channel structure.Na3EuSi6O15. 1.47H2O along the [010] axis along the surface of the surface, and the study of the thermal stability and the fluorescence properties of the 5,6 element ring along the [001] direction. It shows that its structure is still stable at 800 C and shows red light emission. These results show that Na3EuSi6O15 1.47H2O is a kind of good thermal stability fluorescent material.
(3) a fluorine containing microporous europium silicate with a new structure was synthesized by the high temperature and high pressure molten salt method with KF 2H2O and KOH as the flux. The chemical composition of the structure was K2EuSi4O10F. through the single crystal X ray diffraction. The structure of the crystal structure.K2EuSi4O10F was determined by the powder X ray diffraction analysis. The structure of the crystal structure composed of the SiO4 tetrahedron is along the b axis. A three-dimensional open skeleton structure with a 6,8 ring channel structure along the b axis along the b axis, which is formed between the tubular chain of the direction and the EuO4F2 eight plane infinite chains arranged along the b axis through the sharing of oxygen atoms at the top. Red fluorescent material of value.
(4) a series of rare earth germanate with 2D layered structure were successfully synthesized by HR-1B-2 LECO high temperature and high pressure hydrothermal reaction device. The structure of K3[LnGe3O8 (OH) 2]. was studied by single crystal X ray diffraction, powder X ray diffraction, EDS, and infrared spectroscopy. The single crystal structure analysis showed that K3[LnGe3O8 (OH) 2] was separated from negative Yin. The two-dimensional layered structure of the subskeleton consists of the GdGe3O8 (OH) 2 monolayers parallel to the direction of the (010) crystal plane formed by the GeO4/GeO4H tetrahedron and the GdO6 eight facets connected by the bridge oxygen. The single layer is connected by the O H. O bond to form [ABAB in the direction of b axis. The study of the fluorescence properties of Co doped samples K3[Gd1-xTbxGe3O8 (OH) 2] (x=0.1,0.3) shows that there is a energy transfer process of Gd3+ and Tb3+ in the fluorescence spectrum. The fluorescence emission spectrum shows the characteristic emission of Tb3+ ions and is a potential green fluorescent material.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TQ133.3
本文编号：2167988
[Abstract]:Rare earth has been widely used in all aspects of life because of its excellent optical, electrical, magnetic and other physical properties. As a traditional material, the research of the synthesis and application of silicate has always been a hot spot for researchers. As a new show of silicate materials, the silicate compounds with regular pore structure have been used in recent decades. Many excellent properties have also been shown in the study, and great potential applications have been shown in catalysis and adsorption. It is a research subject that people are interested in and continuously explore the unique luminescence properties of rare earth elements and microporous silicate homogeneous pore properties. The medium temperature hydrothermal method was synthesized under the temperature of less than 200 C. The reaction vessel was a stainless steel reaction kettle. In this paper, the Quickpress3.0 piston cylindrical high pressure reactor and the HR-1B-2 LECO high temperature and high pressure hydrothermal reaction device were used to try the microporous rare earth silicate with new structure under higher pressure and temperature. The synthesis of germanate compounds was studied. A series of novel rare earth silicates and germanate compounds were successfully synthesized in the range of 0.5~1GPa pressure and 300~700 C temperature range, and their crystal structure and fluorescence properties were studied.
(1) a new Na15Eu3Si12O36 single crystal was successfully synthesized by high temperature and high pressure synthesis. The crystal structure of the single crystal was analyzed by X ray diffraction analysis of single crystal. The results of the single crystal analysis were verified by powder X ray diffraction and X ray energy spectrum analysis. The crystal structure analysis showed that the crystal was composed of [Si6O12]n1 A three-dimensional open framework constructed by the 2n- ring silicate anions and the EuO6 eight sides by sharing the apical O atoms. The structure contains a 6 membered ring channel structure along [010] direction composed of EuO6 eight and SiO4 tetrahedron. The results of single crystal analysis show that Na (2) + and Na (3) + ions are in its structure. The positions were occupied by Eu (2) and Eu (3), and the statistical disordered Eu/Na occupancy disorder had an important effect on the fluorescence properties of Na15Eu3Si12O36, and this result was verified in the test of its fluorescence properties.
(2) the new structure of europium silicate is successfully synthesized at high temperature and high pressure. The chemical composition of the Na3EuSi6O15. 1.47H2O. single crystal X ray diffraction crystal structure analysis shows that the crystal is a three dimensional open skeleton structure.SiO4 four formed by the interaction of EuO7 polyhedron between the wavy SiO4 tetrahedron monolayers. The structure of the 4,8 element ring along the [100] direction, formed by the EuO7 polyhedron and SiO4 tetrahedron, and the 5,6 element ring path along the [001] direction in the three-dimensional skeleton structure of the 4,5,6,8 element ring channel structure.Na3EuSi6O15. 1.47H2O along the [010] axis along the surface of the surface, and the study of the thermal stability and the fluorescence properties of the 5,6 element ring along the [001] direction. It shows that its structure is still stable at 800 C and shows red light emission. These results show that Na3EuSi6O15 1.47H2O is a kind of good thermal stability fluorescent material.
(3) a fluorine containing microporous europium silicate with a new structure was synthesized by the high temperature and high pressure molten salt method with KF 2H2O and KOH as the flux. The chemical composition of the structure was K2EuSi4O10F. through the single crystal X ray diffraction. The structure of the crystal structure.K2EuSi4O10F was determined by the powder X ray diffraction analysis. The structure of the crystal structure composed of the SiO4 tetrahedron is along the b axis. A three-dimensional open skeleton structure with a 6,8 ring channel structure along the b axis along the b axis, which is formed between the tubular chain of the direction and the EuO4F2 eight plane infinite chains arranged along the b axis through the sharing of oxygen atoms at the top. Red fluorescent material of value.
(4) a series of rare earth germanate with 2D layered structure were successfully synthesized by HR-1B-2 LECO high temperature and high pressure hydrothermal reaction device. The structure of K3[LnGe3O8 (OH) 2]. was studied by single crystal X ray diffraction, powder X ray diffraction, EDS, and infrared spectroscopy. The single crystal structure analysis showed that K3[LnGe3O8 (OH) 2] was separated from negative Yin. The two-dimensional layered structure of the subskeleton consists of the GdGe3O8 (OH) 2 monolayers parallel to the direction of the (010) crystal plane formed by the GeO4/GeO4H tetrahedron and the GdO6 eight facets connected by the bridge oxygen. The single layer is connected by the O H. O bond to form [ABAB in the direction of b axis. The study of the fluorescence properties of Co doped samples K3[Gd1-xTbxGe3O8 (OH) 2] (x=0.1,0.3) shows that there is a energy transfer process of Gd3+ and Tb3+ in the fluorescence spectrum. The fluorescence emission spectrum shows the characteristic emission of Tb3+ ions and is a potential green fluorescent material.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TQ133.3
【参考文献】
相关期刊论文 前1条
1 邓宇航;宋文申;董伟乐;代如成;王中平;张增明;丁泽军;;White light emission of Eu~(3+)/Ag co-doped Y_2Si_2O_7[J];Journal of Rare Earths;2014年09期
本文编号：2167988
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