纳米晶(CeO2)1-x(BiO1.5)x固溶体的水热合成与离子输运性质研究

在240℃水热体系中首次合成出系列纳米晶固溶体(CeO₂)_1-x(BiO_1.5)_x(x=0.0～0.50).产物采用X射线衍射,扫描电子显微镜和X射线光电子能谱仪进行表征.Bi₂O₃在CeO₂中的固溶限约为50%.所有固溶体结晶属立方萤石结构,粒度范围为10～18nm.当Bi₂O₃掺杂量小于固溶限时,于800℃烧结不会导致结构转变.而对于(CeO₂)_0.5(BiO_1.5)_0.5,于800℃在空气中烧结将导致固溶限降低.Bi₂O₃含量低于固溶限时,固溶体只具有体电导,而(CeO₂)_0.6(BiO_1.5)_0.4的总电导可分为体电导和晶界电导.体电导为氧离子,而晶界为来自电极的银离子.     

纳米晶（CeO2）1—x（BiO1.5）x固溶体的水热合成与离子输运性 …

在２４０℃水热体系中首次合成出系列纳米晶固溶体（ＣｅＯ２）１－ｘ（ＢｉＯ１．５）ｘ（ｘ＝０．０￣０．５０）。产物采用Ｘ射线衍射,扫描电子显微镜和Ｘ射线光电子能谱仪进行表征。Ｂｉ２Ｏ３在ＣｅＯ２中的固溶限约为５０％。所有固溶体结晶属立方萤石结构,粒度范围为１０￣１８ｎｍ。当Ｂｉ２Ｏ３掺杂量小于固溶限时,于８００℃烧结不会导致结构转变。而对于（ＣｅＯ２）０．５（ＢｉＯ１．５）０．５,于８００℃在空气中     

Na2SO4辅助水热合成SnO2纳米晶

系统地研究了以SnCl₄·5H₂O为原料，以Na₂SO₄为矿化剂，采用水热法在较低温度下和较短的反应时间内制备结晶良好并均匀分散的SnO₂纳米晶。采用X射线衍射(XRD)、透射电子显微镜(TEM)、红外光谱(IR)等技术对水热反应的晶化过程进行了分析。结果表明：在Na₂SO₄存在的情况下，在120 ℃反应4 h 即可制备得到晶粒细小，分散性能良好的SnO₂纳米晶。XRD衍射峰峰宽随水热温度的升高或反应时间的延长而变窄，结晶性提高。TEM结果表明产物颗粒小、分散性能良好。水热反应温度和反应时间对产物结晶度和粒径有明显的影响。对Na₂SO₄在反应过程中的作用机理进行了分析。     

(ZrO2)1-x(Yb2O3)x纳米晶的水热法合成及其烧结体的电性能

(ZrO₂)_1-x(Yb₂O₃)_x (x=0.07, 0.09, 0.11) nanocrystallites were hydrothermally prepared in basic media by using co-precipitated Zr(OH)₄ and Yb(OH)₃ as precursor. The nanocrystallites have small particle sizes of 5.8~7.5 nm, narrow size distribution, less agglomeration and high sinterability. The oxide-ionic conduction properties of the prepared ceramics were investigated by means of AC impedance spectroscope, oxygen concentration cell at 600~1 000 ℃. The results show that the ceramic with x=0.09 is superior to the ceramics with x=0.07 and 0.11 in oxide-ionic conduction.     

(ZrO2)0.92(Gd2O3)0.08纳米晶的水热合成及其烧结体的电性能

用新制备的(Gd，Zr)(OH)_x·yH₂O共沉淀作前驱体，在强碱性介质中用水热法合成了(ZrO₂)_0.92(Gd₂O₃)_0.08纳米立方晶，考察了反应温度、pH值等水热反应条件对纳米晶粒大小的影响。将(ZrO₂)_0.92(Gd₂O₃)_0.08     

立方晶型Sb2O3纳米晶的合成及光催化性能

采用沉淀法合成了立方晶型Sb2O3纳米晶,通过X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、紫外-可见漫反射光谱(UV-Vis DRS)和电子自旋共振谱(ESR)等对样品进行了详细的表征。以紫外光光催化降解甲基橙为反应模型评价了样品的光催化性能。结果表明:沉淀法合成的立方晶型Sb2O3纳米晶颗粒小,表现出良好的光催化性能。对立方晶型Sb2O3纳米晶光催化降解甲基橙的原因进行了探讨,并提出了降解甲基橙的反应机理。     

高质量尺寸可调CuFeS2纳米晶的合成与光电性质

制备了单分散性良好且尺寸可调的具有荧光性质的CuFeS2纳米晶,利用紫外-可见吸收光谱(UVVis)、荧光光谱、透射电子显微镜(TEM)、X射线粉末衍射(XRD)、元素分析和光电流测试等技术对其组分和结构进行了表征,分析了CuFeS2纳米晶尺寸变化对吸收光谱和光电响应行为的影响规律.随着CuFeS2纳米晶尺寸增大,其吸收峰位表现出符合量子尺寸效应的相应红移;具有荧光性质的CuFeS2纳米晶可控制备预示其在生物医学成像和光电器件等领域具有应用前景.     

配合物[Co(phen)2(m-chlorobenzoic acid)2·(H2O)]·(H2O)2的水热合成、晶体结构电化学分析

The title complex has been synthesized with m-chlorobenzoic acid, 1,10-phenanthroline and cobalt perchlorate anhydrous in the solvent mixture of water and methanol. Crystal data for this complex: triclinic, space group P1, a=0.870 7(3) nm, b=1.284 4(4) nm, c=1.692 9(5) nm; α=75.430(5)°, β=77.562(5)°, γ=86.346(5)°, V=1.789 4(9) nm³, D_c=1.456 g·cm^-3, Z=2, F(000)=806. Final GooF=1.065, R₁=0.068 4, wR₂=0.127 5. The crystal stru-cture shows that the Cobaly ion is coordinated with four nitrogen atoms from two 1,10-phenanthroline molecules and two oxygen atoms from one m-chlorobenzoic acid molecule and one water molecule respectively, forming a distorted octahedral coordination geometry. The cyclic voltametric behavior of the complex is also reported. CCDC: 619087.     

SnO2纳米晶的水热合成及其气敏特性

SnO2 nanocrystal with different crystalline sizes were prepared with SnCl2 2H2O and H2O2 raw materials by a hydrothermal process. The synthesized powders at different reaction temperatures were characterized by means of powder X-ray diffraction, transmission electron microscope, specific surface area and gas sensitivity measurements. The results revealed that the pure SnO2 nanocrystallites synthesized at 120 ℃ have high specific surface area （210.3 m2/g）, and show a high sensitivity to C2H5OH gas. Both traits are beneficial in gas-sensitive detection application.     

一维链状配位聚合物{[Cd2(1，8-nap)2(H2O)2](bpp)2}n的水热合成、晶体结构及荧光性质

The title complex, {[Cd₂(1,8-nap)₂(H₂O)₂](bpp)₂}_n(1), a cadmium complex based on mixed naphthalene-1,8-dicarboxylate (1,8-nap) and flexible 1,3-bi(4-pyridyl)propane (bpp) ligands, has been hydrothermally synthes-ized. It consists of a one-dimensional chain along c axis, which is derived from dimeric unit [Cd₂(1,8-nap)₂(H₂O)₂] linked by a pair of bpp ligands. In every [Cd₂(1,8-nap)₂(H₂O)₂] dimeric unit, two 1,8-nap act as bridging ligands to connect two Cd(Ⅱ) atoms, forming a sixteen-membered ring. Each Cd(Ⅱ) atom is in a distorted octahedral environment, coordinated by one aqua, two 1,8-nap and two bridging bpp ligands. In addition, two bridging bpp ligands connected two neighboring Cd(Ⅱ) atoms form a twenty-four-membered ring. The TGA and Luminescence property in solid state of complex 1 have been further studied and discussed in this paper. CCDC: 669293.     

Zn(Oxin)2·2H2O纳米晶的固相化学反应合成及表征

随着纳米微粒研究的深入,对纳米超细微粒提出了不同的物理、化学特性需求,制备高纯、超细、均匀的纳米微粒,发展新型的纳米材料,就显得非常重要,而解决问题的关键在于研究、发展新的合成技术.通常,纳米微粒制备的要求是:表面洁净;粒子形状及粒径、粒度分布可控,防止粒子团聚;易于收集;有较好的稳定性;产率高.     

纳米结构MnO2的水热合成、晶型及形貌演化

以水热合成方法制备了具有不同微观形貌的纳米结构MnO2, 并以X射线衍射(XRD), 扫描电镜(SEM)和X射线光电子能谱(XPS)等方法对其进行了表征. 跟踪考察了二氧化锰的晶型及微观形貌随水热反应时间的演变过程, 在Ostwald ripening机理作用下, MnO2晶型转化过程为γ-MnO2, α-MnO2和β-MnO2, 同时形貌由微米球转变为海胆结构、空心海胆结构和纳米线.     

微波溶剂热法合成纳米晶Cu2SnSe4及其结构研究

The nanocrystal Cu₂SnSe₄ was synthesized by the microwave solvothermal technique and characterized by X-ray powder diffraction (XRD), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). Results show that the technique is fast, simple and energy saving, and the average size of the product is 20～30 nm. Optical absorption spectrum of Cu₂SnSe₄ shows that product with a band gap of 2.36 eV is a better semiconductor.     

水热法制纳米CeO2膜及紫外吸收性能研究

以Ce(NO3)3.6H2O和CO(NH2)2为原料,采用水热法在玻璃基质上制备了CeO2纳米膜。研究了水热温度和时间对所制备纳米CeO2薄膜的抗紫外性能的影响。采用XRD、FT-IR、SEM、UV-Vis以及自动椭圆偏振仪等测试手段对CeO2纳米膜及粉体进行了表征。结果表明,水热法制备的薄膜,最佳的水热工艺条件为水热温度130℃加热7 h。在此条件下,制备的薄膜厚度达100nm,晶型较好,膜表面平整度较高,且具有优异的可见光透过性和紫外吸收特性。     

GdF3∶Eu3+/NaGdF4∶Eu3+纳米晶的水热合成及发光性质

采用水热法,以聚乙二醇(400)为分散剂,以NaOH和HNO3溶液调节初始溶液pH值,合成GdF3∶Eu3+和NaGdF4∶Eu3+纳米晶。XRD和SEM结果表明:在酸性溶液(pH=3,5)、中性溶液(pH=7)和碱性溶液(pH=9)中,分别获得具有正交结构的GdF3∶Eu3+纳米晶,GdF3∶Eu3+和NaGdF4∶Eu3+混合晶,六方结构NaGdF4∶Eu3+棒状微米晶。根据Scherrer公式估算pH=3和pH=5时制备纳米晶的一次性粒径分别为49和28 nm。样品的发射光谱结果表明:特征发射峰来自于5D2、5D1、5D0到7FJ跃迁。在主晶相为GdF3样品中,主发射峰来自于Eu3+的5D0→7F1的磁偶极跃迁;晶相为NaGdF4样品的主发射峰来自于Eu3+的5D0→7F2电偶极跃迁。5D0→7F1和5D0→7F2跃迁发射相对强度比值显示:Eu3+在NaGdF4晶体中的格位对称性下降。激发光谱显示出Gd3+和Eu3+具有较好的能量传递。     

高介电常数TiO2纳米晶的表面态研究

将钛酸四丁酯和硬脂酸在熔融状态下混合均匀后置于冷水浴中,使其凝固成凝胶,通过控制烧结过程中氧气的含量,成功地制备出粒度均匀、介电性能好的纳米晶TiO2.通过采用X射线光电子能谱和表面光电压谱对纳米晶TiO2表面状态的分析发现,材料表面存在大量的氧空位缺陷,暴露在粒子表面上的主要是一些金属Ti4+.纳米材料的这种表面状态对其极化性质具有重要的影响,使其在接近静态条件下的低频介电常数远大于常规材料的介电常数.     

Cu2ZnSnS4纳米晶微球的制备及其表征

以乙二醇为溶剂,采用溶剂热法合成出由纳米晶组装而成的Cu2ZnSnS4(CZTS)微球。采用X射线衍射仪(XRD)、拉曼光谱仪(Raman)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、紫外-可见漫反射光谱(DRS)对所得微球的结构与成分、颗粒大小与形貌和光学性质进行了测试分析。研究结果表明:溶剂热法制得的CZTS粉体具有四方晶相结构,微球由纳米晶组装而成,对可见光有良好的吸收;随着反应时间的增加,颗粒尺寸逐渐增大,且对形貌有一定影响;此外,文中还对CZTS微球的形成机理做了推测。     

Cu2(μ-dppb)2(μ-Cl)2的合成、晶体结构及非线性光学性质

The complex Cu₂(μ-dppb)₂(μ-Cl)₂ has been synthesized from the reaction of CuCl， dppb and (n-Bu)₄NCl. The crystal belongs to the triclinic with space group P1. The unit cell parameters are: a=9.939(4)?， b=10.083(6)?， c=14.104(5)?， α=76.46(3)°， β=71.02(2)°， γ=70.87(5)°. The single crystal X-ray diffraction analysis reveals that it has a bi-ring structure with a symmetry center at the middle of two Copper atoms. The outer ring is a 14-membered ring of Cu-dppb-Cu-dppb， and the inner ring is a 4-membered ring composed of two Cl^- and two Cu(Ⅰ). Investigation of third-order optical nonlinearity shows that it exhibits considerable nonlinear absorptive and self-defocusing effect with α₂=1.75×10^-13m·W^-1 and n₂=3.19×10^-18m²·W^-1. CCDC: 193113.     

[Ni(phen)2(3,5-DMBA)](m-MBA)2(H2O)2配合物的合成、晶体结构及电化学分析

The title complex of nickel (II) with 3,5-dimethylbenzoic acid, m-methylbenzoic acid and 1,10- phenanthroline was synthesized and characterized. Crystal data for this complex: triclinic, space group P1, a=1.198 5(2) nm, b=1.315 3(2) nm, c=1.531 8(3) nm, α=92.602(3)°, β=103.292(3)°, γ=114.849(3)°, V=2.104 7(6) nm³, D_c=1.361 g·cm^-3, Z=2, F(000)=902, final GooF=1.071, R₁=0.067 2, wR₂=0.155 5. The crystal structure shows that the nickel ion is coordinated with four nitrogen atoms of two 1,10-phenanthroline molecules and two oxygen atoms of one 3,5-dimethyl benzoic acid molecule, forming a distorted octahedral coordination geometry. The cyclic voltametric behavior of the complex was also investigated. CCDC: 286966.