Nanoporous Oxides and Organic-Inorganic Hybrid Materials for Catalysis and Biomedical Applications

具有在1-100 nm范围内的良好限定的孔的纳米材料，即纳米孔，由于在工业催化、环境修复以及作为用于药物/基因递送的生物相容性载体的应用前景而引起极大兴趣。特别地，介孔材料被定义为无机骨架（例如，二氧化硅、金属氧化物、碳），其包含通常在2和15 nm之间的大通道或笼的周期性阵列。该孔径范围提供高表面积和高孔体积，使得这些材料成为多用途催化剂或催化剂载体和生物活性物质的潜在宿主/转运体。 该研究计划的主要目标是：1）开发新的高活性和低成本的非贵金属基催化剂系列，用于可持续的化学生产和能源相关应用（例如，H2生产，电催化）;和2）设计生物相容性纳米多孔杂化材料，其结合了所需的官能团并具有用于生物医学应用的足够的结构和粒度（例如，药物递送）。除了合成和功能化，重点将放在评估催化剂和生物材料的性能和结构-性能关系的调整。介孔二氧化硅材料，例如，MCM-48，SBA-15，可以通过模板法结合结构导向胶束聚集体和无机溶胶-凝胶过程容易地制备，导致具有明确尺寸和形状的特定纳米孔的形成。这些（纳米）结构代表了催化剂和药物输送系统设计的一个很好的起点。模板介孔二氧化硅被认为是无毒的，并且化学和热稳定的。它们的表面硅烷醇基团允许固定各种各样的官能团。此外，可以定制孔结构（尺寸、形状）以优化吸附和扩散参数。此外，可以控制材料颗粒的形态和尺寸以形成胶体（纳米）球或膜。根据目标应用，不同的官能化方法将应用于介孔二氧化硅（例如，通过浸渍或包封插入金属阳离子和氧化物纳米颗粒;有机硅烷的空间选择性接枝;与功能性（生物）聚合物的缀合）。不含二氧化硅的高表面积混合金属氧化物组合物（例如，Cu、Ni、Mn、Zn等）也将使用纳米铸造工艺，一种基于将金属盐浸渍到二氧化硅的孔中，用作硬模板（随后除去二氧化硅）的方法，或通过使用纳米结构的层状氢氧化物前体来制备。除了二氧化硅和氧化物，介孔碳载体将通过二氧化硅纳米铸造和表面活性剂辅助合成来合成，然后改性以引入金属阳离子/氧化物位点。在催化方面，混合金属CuO基材料（二氧化硅或碳负载，或作为纯混合金属氧化物）将在各种重要反应中进行研究，例如，用于H2生产的液相中的H2储存介质的转化，甘油的选择性氢解。对于药物递送，我们将主要关注使用介孔有机硅纳米颗粒（尺寸在30和200 nm之间），在其外表面上用生物相容性聚合物（PEG，蛋白质）功能化，用于抗癌药物（静脉内）和肽类药物（口服）的递送和靶向释放。预计新的催化剂和治疗装置将导致潜在的可销售技术，这些技术对加拿大涉及能源和生产、工业化学、保健和制药或环境补救的各种行业都有意义。

Nanomaterials with well-defined pores in the range of 1-100 nm, i.e. nanopores, are of great interest because of prospects of application in industrial catalysis, environmental remediation, and as biocompatible carriers for drug/gene delivery. Mesoporous materials, in particular, are defined as inorganic frameworks (e.g., silica, metal oxides, carbon) containing periodic arrays of large channels or cages usually comprised between 2 and 15 nm. This range of pore size provides high surface area and high pore volume, making these materials versatile catalysts or catalyst supports and potential hosts/transporters for bioactive substances. The primary objectives of this research program are: 1) to develop new families of highly active and low-cost non-noble metal-based catalysts, to be used for sustainable chemical production and energy-related applications (e.g., H2 production, electrocatalysis); and 2) to design biocompatible nanoporous hybrid materials incorporating desirable functional groups and possessing adequate structure and particle size for biomedical applications (e.g., drug delivery). In addition to synthesis and functionalization, emphasis will be put on assessing the performance of the catalysts and biomaterials and the tuning of the structure-property relationships. Mesoporous silica materials, e.g., MCM-48, SBA-15, can easily be prepared through templating methods combining structure-directing micellar aggregates and inorganic sol-gel process, leading to specific formation of nanopores with well-defined size and shape. These (nano)structures represent an excellent starting point for the design of catalysts and drug delivery systems. Templated mesoporous silicas are considered non-toxic, and chemically and thermally stable. Their surface silanol groups allow fixation of a great diversity of functionalities. Moreover, tailoring of pore structure (size, shape) is possible in order to optimize adsorption and diffusion parameters. Also, morphology and dimension of the material particles can be controlled to form colloidal (nano)spheres or films. Depending on the application targeted, different functionalization approaches will be applied to mesoporous silica (e.g., insertion of metal cations and oxide nanoparticles via impregnation or encapsulation; spatially-selective grafting of organosilanes; conjugation with functional (bio)polymers). Silica-free high-surface-area mixed metal oxide compositions (e.g., Cu, Ni, Mn, Zn, etc.) will also be produced, using the nanocasting process, a method which is based on impregnation of metal salts into the pores of silica, serving as a hard template (followed by silica removal), or by using nanostructured layered hydroxide precursors. In addition to silica and oxides, mesoporous carbon supports will be synthesized both via silica nanocasting and by surfactant-assisted synthesis, and then modified to introduce metal cation/oxide sites. In catalysis, mixed metal CuO-based materials (silica- or carbon-supported, or as pure mixed metal oxides) will be studied in diverse important reactions, e.g., conversion of H2 storage media in liquid phase for H2 production, selective hydrogenolysis of glycerol. For drug delivery, we will mainly focus on using mesoporous organosilica nanoparticles (size between 30 and 200 nm), functionalized with biocompatible polymers (PEG, proteins) on their external surface, for delivery and targeted release of anti-cancer drugs (intravenous) and peptidic drugs (oral delivery). It is anticipated that the new catalysts and therapeutic devices will lead to potentially marketable technologies of interest to a wide variety of Canadian industries dealing with energy resources and production, industrial chemistry, healthcare and pharmaceuticals, or environmental remediation.