【作者】 王吉清；

【导师】 邓风；

【作者基本信息】 中国科学院研究生院（武汉物理与数学研究所） ， 无线电物理， 2005， 博士

【摘要】 本论文围绕固体核磁共振（SSNMR）技术在多相催化领域中的应用这一主题,在一些固体酸催化体系的合成、修饰以及NMR表征方面,进行了一些基础性的研究。以Y型沸石前驱体与有机硅氧烷为硅源,通过共水解-缩聚的方法合成了具有高水热稳定性的巯基（-SH）和磺酸基（-SO₃H）官能化的MSU型介孔硅基材料。Y型沸石前驱体主要由硅酸钠制备而来,这样一种合成途径既提高了有机-无机复合介孔硅基材料的水热稳定性,又降低了材料的合成成本。采用四氯化锡（SnCl₄）和钼酸铵为原料,通过浸渍法合成了在氧化锡上担载钼物种的（MoO₃/SnO₂）催化剂,这是一种在工业上有着重要应用的氧化催化剂,同时又是一种固体酸。应用固体核磁共振技术、探针分子技术和理论计算方法,结合XRD、N₂吸脱附等手段,对磺酸基官能化的介孔硅基材料（MSU-SO₃H）的结构和表面酸性进行了详细的研究。研究结果表明,磺酸基被成功引入到介孔MSU的骨架上,当有机硅组分MPTMS的含量低于30%时,MSU的介孔结构能得到保持。我们合成的MSU-SO3H催化剂具有纯的Brφnsted酸性,酸强度和酸浓度略低于微孔的HZSM-5分子筛。鉴于其介孔结构、相对高的热稳定性和较强的酸性,磺酸基官能化的MSU材料有望应用于一些涉及较大分子的酸催化过程。应用固体核磁共振技术、探针分子技术和理论计算方法,对钼组分与SnO₂间的相互作用、MoO₃/SnO₂催化体系的结构和一些重要性质进行了系统研究。结果表更多还原

【Abstract】 This dissertation is concentrated on the applications of solid-state NMR techniques to heterogeneous catalysis. Some fundamental studies on synthesis, modifications and characterizations of solid acid catalyst matrials have been carried out.Using zeolite Y seeds and organotrialkoxysilane as silica sources, hydrothermally stable thiol- and sulfonic functionalized mesoporous silicas of MSU structure were prepared by a one-pot synthesis involving co-condensation of organotrialkoxysilane and tetraalkoxysilane and post oxidation. It should be noted that inexpensive reactant, mainly including sodium silicate and sodium aluminate, used in the preparation of zeolite Y seeds provided a low-cost route for the synthesis of hydrothermally stable organo-functionalized mesoporous silicas.Tin oxide supported molybdena （MoO₃/SnO₂） was prepared by impregnation process using SnCl4.xH2O and ammonium heptamolybdate as initial materials. MoO₃/SnO₂ is a widely used catalyst for oxidation reactions, and a solid acid as well.The structure and acidity of sulfonic group functionalized mesoporous materials with MSU structure were characterized in detail using multinuclear NMR technique in combination with other approaches such as XRD, N₂ adsorption and desorption, as well as density function theory （DFT） calculation. Our experimental and theoretical calculation results indicate that functionalized MSU-SO3H materials with well-ordered mesostructure have been successfully synthesized and the materials have acid strength slightly weaker than that of microporous zeolite HZSM-5. It can be expected that MSU-SO3H may probably satisfy some catalytic applications involving larger molecules更多还原