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题名	新型钒硼酸盐和钒酸盐化合物的合成、结构和性能研究
作者	高君宇
学位类别	硕士
答辩日期	2012-05
授予单位	中国科学院研究生院
授予地点	北京
导师	潘世烈
关键词	钒硼酸盐 高温溶液法 粉末X射线衍射 单晶结构 性质
学位专业	微电子学与固体电子学
中文摘要	钒酸盐作为一类重要的激光晶体，人们已经对其进行了广泛的研究。硼酸盐是一类具有优异光学性能的材料，由于其在光电子器件及通讯继续领域的潜在的应用引起了极大的关注。近年来，人们希望将钒酸盐和硼酸盐的优异性能结合起来合成新型的矾硼酸盐化合物。该思路引起了人们浓厚的兴趣，有关此类化合物的合成和性质研究陆续有文献报道。 本论文采用高温溶液法探索新型钒硼酸盐晶体，成功合成了一种新型的钒硼酸盐晶体Pb4VBO8，在实验过程中还得到了一种钒酸盐晶体Pb4BiVO8，然后通过单晶衍射技术对它们的结构进行了解析。在本论文中，我们对它们的合成，晶体生长，热稳定性，红外光谱，电子结构等性能进行介绍。 1. Pb4VBO8化合物 采用高温溶液法得到了PbO-V2O5-H3BO3体系中的第一个化合物Pb4VBO8。Pb4VBO8属于单斜晶系，空间群为P21/c (No. 14)，a = 10.4047(5) Å, b = 7.0906(4) Å, c = 12.8968(7) Å, β =113.128(3) °, Z = 4，R1 = 0.0261, wR2 = 0.0628。该化合物为一个三维网络状结构，所有的Pb-O多面体相连构成一个层状结构，所有的B原子形成孤立的平面BO3基团，填充在Pb-O多面体形成的层内。层与层之间通过与VO4共享O原子的方式相连。该化合物为同成分熔融化合物。紫外吸收截止边为368 nm。该化合物为为间接带隙，禁带宽度为2.939 eV。 2. Pb4BiVO8化合物 采用高温溶液法，在PbO-Bi2O3-V2O5体系中得到了化合物 Pb4BiVO8并解析了单晶结构。Pb4BiVO8属于三斜晶系，空间群为P (No. 2)，a = 6.2299(11) Å, b = 7.6128(14) Å, c = 10.4612(19) Å, α = 100.391(2)°, β =102.189(2)°, γ = 90.031(2)°, Z = 2。R1 = 0.0371, wR2 = 0.0953。该化合物为层状结构，所有的Pb-O多面体相连构成一维链。所有的Bi原子与V原子通过共享O原子的方式相连，构成一维[BiVO6]链。这两种链互相平行，通过共享O原子的方式相连构成层状的结构。该化合物为同成分熔融化合物。紫外吸收截止边为420 nm。该化合物为直接带隙，禁带宽度为1.256 eV。
英文摘要	As a kind of important laser crystal, vanadates have been researched extensively. Borate is a kind of materials which have excellent optical properties. They have received great attention due to their potential applications in optoelectronic devices and modern communication technology. In recent years, a series of vanadium borate crystals have been obtained through standard solid-state reactions. We hope that vanadium borate crystals could have the advantages of vanadate and borate. The compounds of vanadium borate have been reported in the literature. The first compound Pb4VBO8 in the PbO-V2O5-H3BO3 ternary system has been synthesized. Its structure was solved by single crystal X-ray diffraction analysis. The crystal structure of Pb4BiVO8 has also been successfully solved by single-crystal X-ray structural analysis. In this paper, we describe their synthesis, crystal structure, thermal stability, infrared spectrum and electronic structure. 1. Pb4VBO8: The first compound Pb4VBO8 in the PbO-V2O5-H3BO3 ternary system has been synthesized. It crystallizes in a monoclinic space group P21/c with a = 10.4047(5) Å, b = 7.0906(4) Å, c = 12.8968(7) Å, β =113.128(3)°, Z = 4 and R1 = 0.0261, wR2 = 0.0628. All the Pb atoms are connected by O atoms forming two-dimensional layers. The BO3 triangles fill in the intralayer. V atoms are located between these layers to balance charge and also to hold the layers together through coordinating with oxygen atoms. The layers are connected by VO4 to form three-dimensional framework. Thermal analysis and powder X-ray diffraction technique prove that Pb4VBO8 is an incongruent melting compound. Diffuse reflectance spectrum indicates that the UV cutoff edge for the Pb4VBO8 crystal is about 368 nm. Pb4VBO8 is a indirect gap crystal with the gap Eg = 2.939 eV. 2. Pb4BiVO8: The crystal structure of Pb4BiVO8 has been successfully solved by single-crystal X-ray structural analysis. Pb4BiVO8 crystallizes in the triclinic space group P (No. 2) with a = 6.2299(11) Å, b = 7.6128(14) Å, c = 10.4612(19) Å, α = 100.391(2)°, β =102.189(2)°, γ = 90.031(2)°, Z = 2 and R1 = 0.0371, wR2 = 0.0953. It consists of one-dimensional [BiVO6] chains parallel to the b axis. All the Pb atoms are connected by O atoms forming one-dimensional chains. Its structure consists of Pb-O polyhedra that are bridged by one-dimensional [BiVO6] chains through their vertex oxygen atoms to form infinite two-dimensional layers. Thermal analysis and powder X-ray diffraction technique prove that Pb4BiVO8 is a congruently melting compound. Diffuse reflectance spectrum indicates that the UV cutoff edge for the Pb4VBO8 crystal is about 420 nm. Pb4VBO8 is a direct gap crystal with the gap Eg = 1.256 eV.
内容类型	学位论文
源URL	[http://ir.xjipc.cas.cn/handle/365002/4377]
专题	新疆理化技术研究所_材料物理与化学研究室
作者单位	中国科学院新疆理化技术研究所
推荐引用方式 GB/T 7714	高君宇. 新型钒硼酸盐和钒酸盐化合物的合成、结构和性能研究[D]. 北京. 中国科学院研究生院. 2012.

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