【作者】 唐兰勤；

【导师】 王子忱；

【作者基本信息】 吉林大学 ， 物理化学， 2009， 博士

【摘要】 本论文在综述国内外ZnO及钇稳定化氧化锆(YSZ)纳米粒子研究现状的基础上,从化学及材料的角度,发展了低温常压液相一步法制备ZnO及YSZ纳米颗粒的技术,利用各种控制方法和新的合成路线得到了一系列具有特殊形貌、表面特性的氧化物材料。首先,以可溶性的锌盐、锆盐为原料,控制反应条件使中间产物Zn(OH)2、ZrO2·nH2O之间发生脱水作用,在液相中一步生成目标氧化物纳米粒子。另外以微溶的固体前驱体为原料,在水相中直接以固相转移的方式直接得到了球形、片形等一系列形貌特征的ZnO粒子。其次在有机小分子的协调作用下,得到了组元形貌可控的ZnO自组装体。将方法进一步扩展,还得到了系列表面特性的氧化物材料,可以直接应用与系列高分子中制成复合材料。此外还对合成的氧化物材料进行了PL、Raman等光学研究,有望指导未来光催化研究。更多还原

【Abstract】 ZnO and YSZ nanopowders are important semiconductor materials, which have broad application prospects. It is known that nanostructures with controllable sizes and shapes are important from both fundamental applied and technological viewpoints. It is a longtime and important subject to improve the preparation methods and technologies. Here, we develop the wet chemical techniques and synthesize series of oxide materials under relative mild condition (low temperature, normal air pressure). And materials with special morphologies and surface properties are reported.First, a simple one-step wet chemical method for the synthesis of ZnO and YSZ nanopowders is reported. In the presence of NaOH, ZnO nanoparticles can be obtained directly through the dehydration reactions between intermediate products of Zn(OH)2. At the same time, dehydration will be promoted by increasing the reaction temperature, and therefore the reaction time is shortened. As to the synthesis of tetragonal YSZ nanoparticles, NaOH also plays an important role as catalyst, which induces the dehydration reactions between ZrO2·nH2O. The one-step solution-based chemical method does not only shorten the reaction time, but also reduce the energy consumption.Second, series ZnO particles like flowers, slices and spheres, are successfully produced by precipitation transformation process, which is conduced by the chemical etching actions of base to insoluble precursors. The solid precursors play an important role in the slow-release of Zn2+ ions, and influence the subsequent formation of ZnO particles. Compared with traditional thermal decomposition method, this kind of solution-based method is facile to obtain series inorganic particles with various morphologies.Third, self-assembled ZnO superstructures are produced by the addition of small organic molecules, and the morphology of building blocks can be tailored facilely. In this method, the pre-formation of ZnO seeds is the key parameters to the synthesis of self-assembled ZnO superstructures. In one way, the small organic molecules regulate the morphology of building blocks; on the other hand, they induce the assembly of these building blocks. This method can also be used to produce other inorganic materials, which could be operated in the absence of polymers.Finally, series ZnO nanopowders with controllable surface properties are successfully produced via the addition of surfactants. The surfactants will react with the surfaces of ZnO particles by their functional groups. As a result, insoluble salts on the surfaces of ZnO are obtained, which finally realizes the surface modification of ZnO particles. In the addition of sodium oleate and octadecyl dihydrogen phosphate, hydrophobic ZnO particles will be obtained, which has a potential application in organic solvents. In the presence of phosphate betaine and polyethylene glycol-based phosphate, the obtained hydrophilic ZnO particles can stabilize in the glycol solution for a long time.更多还原