【作者】 李玥；

【导师】 刘璐；

【作者基本信息】 南开大学 ， 环境工程， 2010， 硕士

【摘要】 纳米材料是指在三维空间中至少有一维处于纳米尺度范围(1-100nm)或由它们作为基本单元构成的材料。当材料的尺寸处于纳米量级时,经常表现出既不同于原子分子、又不同于块体材料的特殊的电、光、磁、力学以至生物学等方面的特征。相对于传统材料,纳米材料的量子尺寸效应、小尺寸效应、表面效应、宏观量子隧道效应和介电限域效应是纳米微粒与纳米固体的基本性质,这些性质使得纳米材料呈现出许多奇异的物理、化学性质。因此,近年来纳米材料得到了越来越多的人们的关注和研究。本文主要研究的是将纳米材料应用于锂离子电池电极材料,同时相关的工作还有应用于光致发光方面。主要通过水热／溶剂热法合成纳米材料,并通过SEM、TEM、HRTEM、XRD、XPS等对合成的纳米材料的形貌和结构进行表征,随后又通过对材料的电化学及光学性能进行测试,来研究它们的应用性能。通过控制合成条件合成的具有花状形貌的NiO微米球,直径在50nm左右。过程中表面活性剂被用作模板提供生长位置和控制晶体生长方向。在具有较均一分布直径的微米球前驱物经过Ostwald熟化过程后,通过灼烧最终得到NiO微米球。独特的纳米结构使得NiO微米球在首次充／放电循环中表现出了出众的蓄锂能力,但循环稳定性还需要进一步提高。通过水热／溶剂热法,通过改变合成条件,合成出两种不同形貌的SnS2纳米结构。通过SEM、TEM、XRD等分别对两种材料进行了表征,并分别对两种材料进行了电化学性质的研究。此方法得到的SnS2纯度高、结晶好,形貌特殊且尺寸均匀,并表现出较好的电化学性能,并有进一步提高的空间。通过水热／溶剂热法合成了Eu2O3介孔球和纳米颗粒线并且通过SEM、HRTEM、XRD等方法对其进行了表征。通过改变溶剂、软模板SDS的加入等合成条件分别得到了球状和线状Eu2O(CO3)2H2O前驱物。通过650℃下对前驱物的煅烧,得到了高纯度的Eu2O3介孔球和纳米颗粒线,它们均显示出很强的光学性能。通过此途径得到的纳米产物表现出了均一的形貌,此合成方法还可以延伸到构造其他介孔性或纳米颗粒组成的线状结构的金属氧化物中去。更多还原

【Abstract】 Nanomaterials are the materials which at least one of their three dimensions is in the nanoscle (1-100nm). When size of the materials is in the nanoscale, these materials often show some special properties in electricity, optics, magnetics, mechanics, and even, biology, and so on, which different from the properties of atoms, molecules and solid materials. Different from conditional materials, the quantum size effect, small-size effect, surface effect, macroscopic quantum tunneling effect, and dielectric confinement effect of nanomaterials are the basic properties of nanoparticles and nanosolids. Besides, these properties make nanomaterials exhibit many particular physical and chemical properties. Therefore, in recent years, nanomaterials drew more and more people’s attention to study with them.This paper mainly studies in the applying of nanomaterials in Li-ion batteries as electrode materials; there is also a relational work in photoluminescence. Nanomaterials were synthesized via hydrothermal/solvothermal method. SEM, TEM, HRTEM, XRD, XPS etc. were used to characterize the morphology and structure of the products. We also carried out some experiments to test the electrochemical and optical properties of obtained nanomaterials.Flower-like NiO microspheres were synthesized via a one-step solvothermal route under controlled conditions, their diameters were～50nm. During this procedure the surfactants were used as templates to supply growth sites and to restrict the growth directions. NiO microspheres were finally obtained with further calcination. The unique nanostructure makes NiO microspheres present superior Li storage performances at initial charge/discharge cycles and further improvement in cyclic stability is still needed.Two different morphology SnS2 nanostructure materials were synthesized through hydrothermal/solvothermal process. SEM, TEM, XRD etc. were used to characterize the morphology and structure of the two products, respectively. And the electrochemical properties of two products were tested. The two types of SnS2 obtained through this process exhibit good purity, good crystallinity, special morphology, and uniform size. The electrochemical properties of two products were relatively good, and there is space for further improvement.Mesoporous Eu2O3 spheres and Eu2O3 nanoparticle-wires were obtained and characterized by HRTEM and X-ray diffraction. By means of adjusting synthetic parameters, for example, different synthetic temperature, adding soft templates SDS, etc, two kinds of precursors such as sphere-like and wire-like Eu2O(CO3)2H2O were obtained respectively. Through calcined precursors at 650℃, the high-quality mesoporous Eu2O3 spheres and Eu2O3 nanoparticle-wires show the strong optical property. Both fluorescence spectrum and XRD pattern prove that synthetic mesoporous Eu2O3 spheres and Eu2O3 nanoparticle-wires own cubic phase structures.更多还原