【作者】 王军；

【导师】 曹洁明；

【作者基本信息】 南京航空航天大学 ， 材料加工工程， 2005， 硕士

【摘要】 随着人们对环境和健康的关注越来越多,科学研究者正在寻求一种可以替代挥发性有机溶剂的“绿色”溶剂。离子液体,一种完全由离子组成熔点在100 °C 以下的液体,使这种设想成为可能,并逐渐引起学术界和工业界的广泛兴趣。因为它具有一些优异的性能:可以忽略的蒸汽压(即不挥发性)、低熔点、很宽的液相温度(可达到 400°C)、低毒性、不燃性、很宽的电势窗和对有机物和无机物良好的溶解性,而广泛的应用于化学合成、分离和电化学。相对于以上的一些成功应用,离子液体在纳米材料合成上的应用还处于起步阶段。 本论文中,首先合成出五种离子液体,然后利用这五种离子液体来合成纳米材料。通过把室温离子液体和微波加热相结合,提出了一种快速、无核、非模板和环境友好的合成纳米材料的绿色方法。因为微波加热能提高反应速率和反应选择性,因此能缩短反应时间并提高反应产率;从微波化学上看,利用离子液体的优势是:室温离子液体有很大的有机阳离子,有机阳离子具有很高的极化率,可以作为一种很好的微波吸收剂,从而导致很快的加热速度,这种快速、低温、无核的环境友好“绿色”的方法避免了烦琐的合成过程,缩短了合成时间,我们利用这种方法合成出了不同形貌的氧化物(ZnO和SnO2)和硫化物(ZnS,CuS,PbS);另外通过溶胶-凝胶法合成出了介孔结构的SiO2和TiO2。通过XRD,BET,SEM,TEM和PL等现代表征手段对产物进行表征,并对合成机理进行了初步的探讨。更多还原

【Abstract】 With growing concern over the environmental impact and health hazards oftraditional volatile organic solvents, researchers continue to search for greeneralternatives. Room-temperature ionic liquids (RTILs), are simply liquids that arecomposed entirely of ions with a melting point below 100°C, have been shown tobe viable substitutes for organic solvents both in academia and industry due totheir negligible vapor pressure, low melting points, wide range of liquidustemperatures (up to 400℃), low toxicity, nonflammability, large electrochemicalwindow, good solvents for many organic and inorganic materials, and high ionicconductively and thermal stability, are widely application in the organic chemicalreactions, separations, and electrochemical. In contrast to their successfulapplications in organic and materials chemistry, the use of RTILs in nanostructressynthesis is still in its infancy. In this paper, we synthesized five different RTILs, and then used the RTILs tosynthesize various nanomaterials. By combining the advantages of both RTILs andmicrowave heating, we report a fast, seedless, template-free and environmentallybenign green route for the production of vairous morphological nanostructures bymicrowave-assisted heating in RTILs. The RTILs consists of cation and anion. Thehigh ionic conductivity and polarizability of cation make it an excellentmicrowave absorbing agent, thus leading to a high heating rate and a significantlyshorten reaction time. The movement and polarization of ions under the rapidlychanging electric field of the microwave result in transient, anisotropicmicro-domains for the reaction system, facilitating the anisotropic growth ofvarious nanostructures. We synthesized various morphologies of ZnO, SnO2 andsulfide, etc. by this method. The products were characterized by XRD, SEM, TEM,PL, and we investigated the morphology variations of nanostructures withdifferent conditions. In additional, we synthesized mesostructured SiO2 and TiO2using sol-gel method in different RTILs and dicussed the possible formationmechanism.更多还原