【作者】 朱建华；

【导师】 俞书宏；

【作者基本信息】 中国科学技术大学 ， 材料物理与化学， 2008， 博士

【摘要】 本论文进一步丰富和发展了模拟生物矿化合成无机仿生材料的方法,研究了合成类自然生物仿生材料的新思路和聚合物诱导的液态前驱物过程。合成了一系列结构新颖独特的纳米线及其图案化生长阵列。利用聚合物添加剂和衬底的协同作用,在温和反应条件下,通过改变实验条件获得了多种新奇形貌的纳米线及其阵列结构。研究结果归纳如下:1.借助微接触印刷技术、聚合物诱导的液态前驱物结晶过程（PILP）和溶液-前驱物-固体（SPS）生长过程,制备了图案化生长的方解石相CaCO₃纳米线阵列。衬底上的有机分子“框架”,使得矿化前驱物可以选择性沉积,并在衬底上形成矿物质薄膜。结晶后的矿物质膜可以很好的保持其原有的形貌及其阵列结构,利用其作为二次生长的模板,生长出方解石相CaCO₃纳米线及其阵列。该纳米线的微结构揭示了其“亚晶”生长过程。该模拟生物矿化合成方法可以被用来生长其它无机晶体材料及其阵列。2.在聚合物及有机染料复合添加剂溶液中,合成了具有高长径比的BaCO₃复合物纳米线。通过研究发现,该复合物纳米线随着矿化时间不同,可以在不同尺度进行有效的自组装。染料分子的引入,使纳米线具备了光致发光的性质,它们以J-聚体的形式存在于纳米空间内,形成周期性的复杂结构。我们通过对生长衬底的选择性修饰,合成了该复合物纳米线的图案化生长阵列。在紫外光照射下,图案化阵列显示微区发光特性。3.采用磷酸化的嵌段共聚物作为晶体生长的调节剂,在BaCO₃矿物质膜上成功的合成了双螺旋及柱体螺旋纳米线。实验中探索了合成该螺旋形纳米线的适宜生长条件,即调控溶液的起始pH值在3.5-4.5之间,借助沉积在OTS有机衬底上的矿物质膜,可以有效的生长出此类螺旋形超结构。该纳米线的生长过程受到了溶液-前驱物-固体（SPS）生长过程及其纳米颗粒微观聚集/组装的双重影响。该合成思路为理解复杂结构的生物矿物材料的合成过程提供一个新的范例;同时,该合成方法有可能被用来合成其它多种结构独特的无机纳米材料。更多还原

【Abstract】 In this dissertation, we have enriched and further developed the biomimetic approach to synthesize inorganic biomaterials. Some new synthesis strategies have been proposed to fabricate novel mineral materials as those in nature. Especially, the combination of a functional polymer with a patterned substrate allows it possible to grow micropatterned nanofibers under mild condition. The main results can be summarized as follows:1. Micropatterned calcite fibers have been fabricated by the combination of microcontact printing, the so-called polymer-induced liquid-precursor （PILP） and solution-precursor-solid （SPS） growth process. Organic frameworks on the substrate enable the mineral precursor deposit on the substrate selectively. Upon subsequent solidification and crystallization, the mineral precursor retains their morphologies and arrays on the substrate, providing a secondary template for patterning the location and morphology of two-dimensional calcite fibers. The detailed structures of novel fibers indicate they are in fact "mesocrystals". This biomimetic approach is expected for patterning growth of other functional inorganic materials in future.2. High aspect ratio, luminescent BaCO₃ nanowires and their micropatterned arrays have been synthesized in the presence of mixed additives of the copolymer and organic dye. The hybrid nanofibers show a time-dependent tendency of self-assembly into ordered structures. Combining with the copolymer, most dye molecules are kept in the nano-space between the nanofibers in a form of J-aggregate. The patterned nanowires display microregions-enhanced photoluminescent property under ultraviolet illumination.3. Double-stranded and cylindrical helical BaCO₃ nanofibers have been synthesized by using a phosphonated block copolymer as additive. The suitable growth conditions for the helical nanofibers have been studied. Most helical nanofibers are favorable to grow from the mineral films on the OTS-coated substrate in the solution with starting pH values from 3.5 to 4.5. A mechanism involving polymer-induced liquid precursors （PILP） and self-assembly process of nanoparticles for the formation of helical BaCO₃ fibers is proposed. These fascinating curved, spiral biomimetic superstructures have same morphologies as biogenic materials in nature. These results provide new insights into understanding of complex biomineralization processes in nature. This synthesis method could be extended to synthesize other inorganic materials with fascinating morphologies and structures.更多还原