【作者】 朱雪梅；

【导师】 谢安建；

【作者基本信息】 安徽大学 ， 无机化学， 2006， 硕士

【摘要】 纳米材料由于其独特的性质和广泛的应用前景，已经成为研究的热点。而表面活性剂在纳米材料的制备中起着重要的作用，如对纳米材料进行表面修饰，控制纳米材料的大小与形貌等。本论文在乙醇—水体系中用一种简单方法制备出表面具有不同有机酸包裹的纳米硫酸钡；分别用微乳液、微乳液／水热、微乳液／超声相结合的方法开展了对不同形貌的稀土磷酸盐纳米粒子的制备研究。具体内容如下： 1、在乙醇—水体系中，用十四酸、十六酸、十八酸作为表面修饰剂，制备了具有不同有机酸修饰的纳米BaSO₄。用傅立叶红外（FT-IR），粉末X衍射（XRD），动态光散射（DLS），透射电镜（TEM），热重分析（TGA）等测试方法分别对所制得的纳米BaSO₄进行了表征。结果表明，在加入一定量的有机酸和少量的氨水的条件下，能得到分散性好，粒径分布均匀的具有有机修饰纳米BaSO₄；十四酸、十六酸、十八酸修饰的BaSO₄纳米颗粒的平均粒径依次为25nm，20nm，16nm，它们均为正交晶系。 2、以乳化剂OP（聚乙二醇辛基苯基醚）／正戊醇／环己烷／水溶液所形成的W／O型微乳液为反应体系，通过改变ω₀（水与表面活性剂的摩尔比），陈化时间，反应液的加入方式，制备了球形和放射针状的纳米PrPO₄和球形的纳米ErPO₄；用十六烷基三甲基溴化铵（CTAB）／正丁醇／正庚烷／水溶液所形成的W／O型微乳液为反应体系，制备了纤维网状的PrPO₄纳米粒子和刺球状的纳米ErPO₄。XRD结果表明反应条件的改变对PrPO₄和ErPO₄的晶型没有影响，所得的PrPO₄均为单斜晶系，ErPO₄均为四方晶系。我们对不同形貌的PrPO₄和ErPO₄的形成机理作了初步探讨。 3、分别用OP（聚乙二醇辛基苯基醚）／正戊醇／环己烷／水溶液所形成的W／O型微乳液体系和十六烷基三甲基溴化铵（CTAB）／正丁醇／正庚烷／水溶液形成的W／O型微乳液体系与水热法相结合，制备了不同形貌的稀土磷酸盐。用透射电镜（TEM）和粉末X-衍射（XRD）对所制的稀土磷酸盐进行表征。结果表明，OP所形成的微乳／水热法制备了PrPO₄纳米棒、DyPO₄纳米棒、EuPO₄纳米更多还原

【Abstract】 Nano-materials have attracted considerable attention due to their unique properties and superior application prospects. Surfactant is widely used in the preparation of nano-materials, such as, surface-modification for nano-materials, control on the size and morphology of nano-materials. In this dissertation, the different organic acid modified nanosized BaSO₄ were synthesized by a simple method in ethanol-water reaction system. The lanthanide orthophosphate with different morphologies were prepared by microemulsion method, microemulsion/hydrothermal method and microemulsion/ultrasonic method. The main results are summarized as follows.1. We prepared nanosized BaSO₄ particles modified with tetradecanoic acid, hexadecanoic acid and stearic acid in ethanol-water reaction system. The nanoparticles were characterized by Fourier transform infrared spectroscopy （FT-IR）, powder X-ray diffraction （XRD）, transmission electron microscope （TEM）, dynamic light scattering （DLS） and thermo gravimetric analysis （TGA）, respectively. The results indicated that the BaSO₄ modified with different organic acid having good dispersion in the presence of a certain concentration NH₃·H₂O and organic acid, the average diameters of barium sulfate were about 25nm, 20nm and 16nm obtained in the reaction system containing tetradecanoic acid, hexadecanoic acid and stearic acid, respectively and the crystalline states of BaSO₄ were all orthorhombic.2. The lanthanide orthophosphates with different morphologies, such as spherical, radicalized needle-like praseodymium orthophosphate （PrPO₄）, spherical erbium orthophosphate （ErPO₄）, were prepared in microemulsion solutions formed by p-octyle polyethylene glycol phenylether （OP）, n-pentanol (C₅H₁₁OH), cyclohexane (C₆H₁₁) and water, through varying the ω₀ （molar ratio of water to surfactant）, aging time and the additional method of reactants. The fibre-net-like PrPO₄ and prickly sphere-like ErPO₄ were synthesized in the microemulsion solution formed by cetyltrimethylammonium bromide （CTAB）. n-butanol （C₄H₉OH）, n-heptane (C₇H₁₆),更多还原