【作者】 杨迎生；

【导师】 徐赛龙；

【作者基本信息】 北京化工大学 ， 应用化学， 2009， 硕士

【摘要】 随着材料科学与技术的发展,科学家正在努力探索运用化学或物理的方法来构建具有特定形貌和孔结构的材料,从而可能实现对某些材料的设计,如新型催化剂载体、大分子聚合物分离膜、生物医药材料和药物载体等,最终调控其应用性能。复合金属氢氧化物（LDHs）是一类可人工合成的、具有二维结构的阴离子型层状功能材料,它们由带有正电荷的主体层板、平衡正电荷的层间阴离子客体和部分水分子组成。其层板元素组成和层间阴离子种类可调的特点能够衍生出很多具有不同物理化学特性的功能性组装体,因此有可能作为高性能催化材料、吸附材料、分离材料、功能性助剂材料、生物材料和医药材料等获得应用。目前,在该研究领域的工作中,LDHs类材料通常是以粉体形式使用,这样就会在实际应用过程中（比如作为催化材料、吸附和分离材料等）产生诸如压力高、传质/传热效率低以及分离困难等问题。因此,关于LDHs类材料的形貌可控制备具有明显的科学意义和实际应用价值。本论文以LDHs类材料的形貌可控制备为目标,重点研究了水滑石@磺化聚苯乙烯复合微球材料的制备及其应用。具体的研究内容和实验结果如下:1.在高电荷、磺酸根改性的聚苯乙烯微球表面,通过表面成核和生长过程在微球表面生长水滑石,而形成均匀的包覆层,其壳层可表现出花状和草莓状的结构,包覆层厚度在40～200nm左右。包覆层的厚度和形貌可以通过改变金属离子和聚苯乙烯微球的浓度来调节;2.垂直取向纳微结构的CoFeFe-LDHs薄膜,经硅烷偶联剂修饰后,表现出优异的超疏水性能,与水的静态接触角高达157.7°。3.系统地考察了疏水化处理后CoFeFe-LDHs水滑石异质微球其抗酸碱性能,研究结果表明:其具有一定的耐酸性,在pH=2的水溶液中,其静态接触角高达158.8°,150s左右其接触角到达稳定,其接触角为141°。而在pH=12的水溶液中,水滑石存在一个溶解再结晶的过程。造成这两种情况的根本原因是氟化后水滑石的耐酸碱性能改变。4.通过SEM表征手段揭示了表面修饰后的CoFeFe-LDHs薄膜产生超疏水性能的内在原因:低温条件下制备的LDHs薄膜较疏松,晶粒之间空隙较大,形成纳微复合结构;并且疏水化处理后薄膜纳微结构基本上没有变化;水滴与薄膜介面上能够容纳较多的空气气囊,从而表现出优异的超疏水性能。5.对CoFeFe-LDHs@sPS复合微球进行程序升温煅烧制备CoFe₂O₄中空微球,通过掺杂水滑石层板的金属元素的实现了对尖晶石磁性的调控;更多还原

【Abstract】 With the development of materials science and technologies,scientists are exploring some methods involving chemistry or physics to construct materials with specific morphology and pore architecture and realizing the design and adjust and control of some functional materials such as new types of catalyst supports,membranes for the separation of large polymers, biomedical materials with macroporosity and drug carriers.Layered double hydroxides（LDHs） are a large family of synthetic anion type of layered materials with two-dimensional nanostructures consisting of positively charged layer with charge balancing anions and water moleculars between the layers.As a result,a large calss of functional isostructural materials with widely varied physicochemical properties can be obtained by changing the nature and molar ratios of the metal elements as well as the type of intercalated anions.Thus,LDHs are promising functional materials for a large number of applications in catalysis,adsorption,separation,functional additives,pharmaceutics and biomaterials.So far,LDHs involved in the above fields such as catalysis,adsorption and separation are usually in powder form,which inevitablly give rise to problems such as high pressure drops, poor mass/heat transfer,poor contact efficiency and difficulties in separation. Thus,it is essential both in science and practice to undertake the morphology control study related to LDHs materials.In the present thesis,we take the morphology control of synthetic LDHs as target and put emphasis onto the preparation of microspherical LDHs.The main results are as follows:1.The polystyrene microspheres with high-charged and acid modified surface by surface nucleation and growth processes formed a uniform coating, and the shell can be shown with the strawberry-shaped flower structure, coating thickness about 40～200nm.The thickness and morphology of coating can be controlled by the metal ions and the concentration of polystyrene microspheres.2.The CoFeFe-LDHs film with vertical orientation and micro-nano structure modified by silane coupling agent have excellent hydrophobic properties and the static water contact angle for 157.7°.3.Systematic study of the hydrophobic treatment of hydrotalcite CoFeFe-LDHs microspheres heterogeneity of its anti-acid-base performance, and the results showed that:it has a certain degree of acid and,the static contact angle as high as 158.8°with pH=2.The contact angle achieved stability in 150s,and the contact angle of 141°.There is a hydrotalcite recrystallization process of dissolution with the aqueous solution of pH=12. Resulted in both cases the fundamental reason is that after fluorination of the acid properties of hydrotalcite-like change.4.The result of CoFeFe-LDHs film with modified surface have a super-hydrophobic properties of the underlying as follows:the LDHs film prepared at low temperature are sparse,and the gap between the larger grains to form a micro-composite structure satisfied;and the thin-film micro-structure treated by hydrophobic satisfied is basically unchanged; because of air ballon between the droplet interface and thin film,the film show the excellent performance of super-hydrophobic.5.After calcining CoFeFe-LDHs@sPS composite microspheres by temperature-programmed calcinations,we can control the CoFe₂O₄ hollow microspheres through hydrotalcite doped metal plate elements for the magnetic spinel.更多还原