【作者】 昌杰；

【导师】 袁孝友；

【作者基本信息】 安徽大学 ， 物理化学， 2010， 硕士

【摘要】 准一维稀土化合物纳米材料主要包括纳米线、纳米棒、纳米带、纳米管、纳米电缆等,由于其独特的结构而具有特殊的光学、磁学等物理性能与化学性能引起了人们的广泛关注。因而寻求简单有效制备准一维稀土纳米材料的手段,并探索其相关性质具有非常重要的意义。本文成功制备了多孔有序的氧化铝膜,并用负压抽滤法在氧化铝模板中组装得到了钕镍氧化物纳米管,研究了溶剂热法制备了氧化钐纳米线。通过各种表征手段(SEM、HRTEM、XRD、VSM、荧光分光光度计等)对制备的一维纳米材料进行了形貌,结构,性质的表征。主要内容如下：(1)采用两步阳极氧化法在硫酸溶液,草酸溶液,磷酸溶液中制备高度有序的孔径为30nm,70nm,120nm,250nm的多孔有序氧化铝膜,并对其四种膜的荧光性能进行了比较,分析了四种多孔氧化铝膜荧光性能有差异的原因。(2)通过负压—抽滤法,成功地在孔径为70nm的多孔阳极氧化铝模板中制备了大面积的尺寸、形状均匀一致的NdxNi1-xOy纳米管阵列。XRD及SAED的结果显示NdxNi1-xOy纳米管阵列是非晶结构。磁滞回线显示易磁化方向是平行于NdxNi1-xOy纳米管阵列的方向,NdxNi1-xOy纳米管阵列具有磁各向异性,且磁各向异性主要是来自于形状各相异性的贡献。荧光发光性能研究表明NdxNi1-xOy纳米管阵列在激发波长为808nm时有两个反斯托克斯峰,它们是由于Nd3+的能级跃迁所导致。(3)以硝酸钐为原料,采用溶剂热法制备了氢氧化钐纳米线,高温煅烧得到氧化钐纳米线,分别采用SEM、HRTEM、XRD、EDS等手段对所合成的氧化钐纳米线进行了形貌、晶形结构和成分的分析,研究了反应条件对氧化钐纳米线形成的影响,并采用荧光分光光度计和振动样品磁强计对其室温下的光致发光性能和磁性能进行了表征。更多还原

【Abstract】 Quasi one dimensional rare earth compound nanostructures such as nanowires, nanorods, nanobelts, nanotubes have attracted intensive attention owing to their unique photoluminescence and maganetic properties, which is related to the 4f shell of rare earth ions and nanostructure effects, for example, surface effect, quantum of size confinement effects. Therefore, it is interesting to seek a facile and high yield synthetic method to fabricate quasi one dimensional nanostructures for further application. In this thesis, PAA template with uniform and large-scale nanopores has been fabricated by two-step anodization, and non-stoichiometric NdxNi1-xOy nanotube arrays have been synthesized in PAA template and the performances of the NdxNi1-xOy nanotube arrays have been investigated. Moreover, a solvothermal method has been developed to synthesis Sm2O3 nanowires.The detailed researches of the thesis are as follows:(1) Porous alumina films with different pore diameters have been fabricated by two-step anodization in different electrolyte (30nm in sulfuric acid,70nm and 120nm in oxalic acid,250nm in phosphoric acid). The morphology and structure of PAA are observed by SEM and XRD, the room temperature photoluminescence properties are characterized by HITACHI (F-4500) Fluorescence Spectrophotometer. The reasons for variation of photoluminescence between PAA films prepared in different electrolyte are investigated.(2) NdxNi1-xOy nanotube arrays have been synthesized in PAA template by filtering at subatmospheric. The images of non-stoichiometric NdxNi1-xOy nanotube arrays and single nanotube are observed by SEM and TEM, respectively. SAED, XRD and EDS are employed to study the morphology and chemical composition of the nanotubes. The hysteresis loops characterized by a vibrating sample magnetometer (VSM) show that the easily magnetized direction of non-stoichiometric NdxNi1-xOy is parallel to the nanotube arrays and there exhibits magnetic anisotropy as a result of the shape anisotropy. The up-conversion of non-stoichiometric NdxNi1-xOy nanotube is investigated using HITACHI (F-4500) high-pressure xenon lamp, the results indicate that the blue up-conversion emission and green up-conversion emission are respectively occurred at 480nm and 534nm, excited by 808nm.(3) We demonstrate the produtcion of Sm2O3 nanowires through a solvothermal method followed by a dehydration process using Sm(NO3)3 as raw materials. Then SEM, HRTEM, XRD, EDS are used to investigate morphology, crystal structure and composition of the products. Room temperature photoluminescence and magnetic properties are also researched by fluorescence spectrophotometer and vibrating sample magnetometer (VSM), respectively. Effects of reaction temperature, solvothermal time and composition of solvent on the formation of nanowires have been discussed.更多还原