【作者】 朱永恒；

【导师】 徐甲强；

【作者基本信息】 上海大学 ， 凝聚态物理， 2013， 博士

【摘要】 有序介孔材料因其在催化、分离、吸附等领域具有重要的应用价值受到了世界范围内科学家们的广泛关注，但其形貌、尺寸、孔径、表面修饰物等对性能有重要的影响。因此，方便客体材料在孔道内扩散和传输的短孔道和规则形貌的介孔材料备受关注。本论文致力于制备具有规则六方片状形貌的和短孔道的介孔材料SBA-15。以其为主体材料进行修饰和组装后得到具有不同功能的介孔材料，利用多种表征技术，对其结构、形貌和性质进行了详细的研究，取得如下研究成果：1.采用水热合成法在酸性条件下合成出规则形貌的介孔材料SBA-15。研究了水热温度、搅拌速度等合成条件对SBA-15孔结构及形貌的影响。经表征：合成试样的孔径尺寸单一，分散性好；其孔道呈六方排列，具有良好的长程有序结构，是典型的有序介孔材料。通过优化实验方案，成功制备出具有规则形貌的新型SBA-15材料，其最大孔径为12.7nm，热稳定性好。研究结果表明：在合成SBA-15时，表面活性剂的疏水链段和亲水链段的比例对聚集体的形貌有很大的影响；水热温度和搅拌速度对非离子型表面活性剂在水溶液中形成棒状胶束的临界胶束浓度(CMC)产生影响，可以导致CMC降低，促使棒状胶束形成六方有序排列；对有序介孔氧化硅SBA-15材料的形貌有显著影响。2.利用后合成的方法，得到具有六方薄片状规则形貌的氨基功能化介孔材料AAPTMS-SBA-15。利用氮气吸附/脱附实验，傅立叶变换红外光谱，X射线衍射，透射电子显微镜和场发射扫描电子显微镜对样品的结构和形貌进行了表征。将氨基功能化的介孔材料SBA-15作为石英晶体微天平（QCM）质量型传感器的敏感材料构建出性能优异的甲醛传感器。实验结果表明：该甲醛传感器具有高的灵敏度和选择性，响应时间为11s，恢复时间为15s，并且该传感器的检出限可达ppm级。本研究为功能化介孔材料AAPTMS-SBA-15开辟了一种新的应用领域。3.以具有六方片状规则形貌的氨基功能化NH2-SBA-15为模板，制备出具有规则形貌的六方片状三氧化钨。利用氮气吸附/脱附实验，傅立叶变换红外光谱仪，X射线衍射，透射电子显微镜和场发射扫描电子显微镜对样品的结构和形貌进行了表征。所制备出的片状三氧化钨对硫化氢（H2S）气体表现出优良的气敏特性，所制得的硫化氢传感器具有灵敏度高，选择性好，响应/恢复时间短，重复性好等优点。本实验的合成方法也为模板法合成其它金属氧化物片状材料提供了参考。4.采用湿法浸渍的方法，成功地将贵金属Pt、Au纳米颗粒均匀的分散到介孔材料SBA-15的孔道中。Pt、Au纳米颗粒的负载量可以随着前驱体氯铂酸或氯金酸溶液的浓度的增加而增加。其颗粒大小可以通过改变SBA-15孔径大小来实现。以4-Mpy为探针分子，研究了不同结构的Au纳米颗粒负载介孔材料SBA-15的SERS效应，发现了这种纳米粒子作为SERS基底在痕量检测和生物鉴定中的应用前景。5.采用“接枝到表面”(graft-to)的方法成功地将羧基甜菜碱类聚合物pCBMA嫁接到介孔材料SBA-15的表面，得到了既能抗非特异性蛋白吸附又能够连接生物分子的双功能化介孔材料SBA-15，所得材料显示出很好的抗非特异性蛋白吸附性能。利用羧基甜菜碱类聚合物表面功能化，将氨基酸Cyclo-[Arg-Gly-Asp-D-Tyr-Lys](cyclic-RGD)成功地嫁接到表面，所得介孔材料SBA-15可以被牛主动脉内皮细胞（BAECs）选择性的摄取。该双功能化介孔材料SBA-15纳米粒子在药物的靶向输运和基因治疗等方面具有潜在的应用价值。更多还原

【Abstract】 Due to the uniform pore structure and high surface areas, ordered mesoporousmaterials (e.g., MCM-41，SBA-15etc.) have been studied extensively in the fields ofcatalysis, separation, adsorption, etc. Methods to tune morphology, pore size andparticle size of the mesoporous materials, as well as how to incorporateheterogeneous atoms (e.g., Pt, Au, etc.) into the framework has become the hot issuefor the purpose of their practical applications. Particularly, mesoporous materialswith short&open channels and uniform morphology have been extensivelyinvestigated because they are more favorable to the mass transfer. The thesis putstress upon the fabrication of mesoporous materials with controllable morphologies.Mesoporous materials SBA-15with uniform hexagonal lamelliform morphology andshort channels was obtained. Several types of functionalized mesoporous materialswith different morphologies, various components and distinct properties havesuccessfully been prepared. A variety of characterization can be applied toinvestigate detailedly the properties of the functional mesoporous materials.Numbers of experimental data have revealed the effects of encapsulatingconcentration of guests on the properties of the materials and the relation betweenexperimental conditions in preparation and the morphologies of the materials. Themain research work and results are summarized as follows.I. Mesoporous silica SBA-15was prepared through a hydrothermal treatment inacid media. The as-synthesized samples show the uniform pore size andlong-distance ordered arrangement of hexagonal structure, which is typicallyordered mesoporous structure. Through the orthogonal experiments, SBA-15with uniform hexagonal lamelliform morphology has been obtained. The biggestpore size is mainly centered on12.7nm. The as-made SBA-15possesses ofgood thermal stability. The crystallization temperature and the stirring rate cangreatly influence the mesostructure and morphology of the ordered mesoporous silica, which has been studied in detail. It can reduce the CMC concentrationand enhance the formation of hexagonal order arrangement of the surfactantmicelles. Reasonable crystallization temperature and stirring rate can help toform the thermally stable SBA-15with the morphology of hexagonal.II. Amine-functionalized SBA-15with uniform morphology and well-definedmesostructure was prepared using a post-grafting route. The morphology,mesostructure and functionality of the materials were characterized by SEM,TEM, SAXS, nitrogen adsorption–desorption, FTIR, and solid-state NMRspectroscopy techniques. The results show that hexagonal lamelliform SBA-15with a uniform particle size and short vertical channels plays two significantroles in uniformly dispersing amine functionalizing groups and effectivelyadjusting the loadings of the functional groups within the mesopore channels. Inorder to confirm the potential application of the hybrids in gas sensors, usingamine-functionalized SBA-15as a sensing material and quartz crystalmicro-balances (QCMs) as a transducer, a ppb-level formaldehyde sensor withhigh sensitivity (response time about11s, the recovery time about15s) andgood chemoselectivity was achieved. This material holds great potential in thearea of rapid, sensitive, and highly convenient formaldehyde detection.III. Nanostructured cubic crystalline tungsten trioxide (WO3) with uniformplate-like morphology was duplicated in a solution phase using a monodispersedhexagonal lamelliform amine-functionalized SBA-15as a template. X-raydiffraction, nitrogen adsorption/desorption, Fourier transformation infraredspectroscopy, solid state NMR spectrometry, transmission electron microscopyand field emission scanning electron microscopy were employed to characterizethe products. The as-prepared crystalline WO3with optimal morphology showedexcellent gas sensing properties upon exposure to H2S gas in practicalapplication. Herein, we developed an excellent H2S sensor with high sensitivity,good selectivity, short response/recovery time and high reproducibility, and presented a novel strategy to template synthesize crystalline metal oxidenanostructures with defined plate-like morphology.IV. In this part, we use simply wet impregnation method to grow gold or platinumnanoparticles only inside the channels of SBA-15mesoporous silica microplates.The gold nanoparticles are closely, well-dispersed inside the channels with thesize2-5nm. The amount of gold nanoparticles inside the channels can be easilycontrolled by simply varying the concentration of gold salt solution. This newapproach could be generalized for the growth of other metallic nanoparticlessuch as Pt, Pd, and Ag inside the channels of the mesoporous materials. Theas-synthesized nanocomposite material exhibits strong SERS effect andtherefore, can be used as a robust SERS-active substrate for chemical andbiological sensing.V. Herein, a biomimetic conjugated polymer containing one non-foulingpoly(carboxybetaine)(pCBMA) chain and one surface-adhesive3,4-dihydroxyphenyl-L-alanine (DOPA) residue group was efficiently grafted to the outersurface of SBA-15using a convenient and robust method. Furthermore,inductively coupled plasma mass spectrometry (ICP-MS) analysis resultsshowed that after SBA-15-DOPA-pCBMAs were conjugated with a targetingCyclo-[Arg-Gly-Asp-D-Tyr-Lys](cyclic-RGD) peptide, uptake by BovineAortic Endothelial Cells (BAECs) was notably increased. Results indicated thatcyclic-RGD functionalized MSNs were able to selectively interact with cellsexpressing αvβ3integrin. Thus, MSNs with DOPA-pCBMAs are promisingstealth multi-functional bio-carriers for targeted drug delivery or diagnostics.更多还原