| Since the discovery of the M41S family of mesoporous molecular in 1992, a great amount of research has been devoted to the potential application of the mesoporous molecular sieves that belong to the M41S family. Mesoporous materials with uniform mesopores (2-50 nm), large surface areas and large pore volumes have attracted widespread attention due to their relevance for applications in many areas, such as energy storage, catalysis, electrochemistry, adsorption, separation and purification water, etc. The discovery of the M41S was rapidly followed by a variety of reports on the inclusion chemistry of these materials. Mesoporous materials have very high surface areas due to a narrow pore size distribution and well-defined pore networks, hence providing a confined space for controlled intrapore inclusion chemistry as hosts. The encapsulation of organic dye molecules in these hosts leads to composite materials with novel optical properties, which enable possible applications as materials for optical data storage, frequency doubling, optical sensing, or photocatalysis. The self-assembly of nanoparticles within the channel system of mesoporous host matrices has opened a new route to the synthesis of nanostructured materials having unique physical and chemical characteristics.　Some of these well defined host–guest systems are known to exhibit better catalytic properties for a number of chemical reactions, as compared to the host or the guest component itself. The formation of host–guest composites of semiconductor nanoparticles, like cadmium (CdS) or lead (PbS) sulfides or cadmium selenide (CdSe), embedded within the mesoropores of inorganic solids has been described up to now and these host-guest exhibit unique physical and chemical characteristics.　So, in this thesis, we focused on the synthesis of nanostructured materials which have unique physical and chemical characteristics and investigated the properties of these nanostructured materials. Porous adsorbents must have large surface areas, such as commercial activated carbons, which have large surface areas (>1200 m2/g). Commercial activated carbons are widely used as industrial adsorbents for separation and purification. They are also used as catalyst supports, electrode materials for batteries, capacitors and adsorbents in biomedical engineering. However, the performance of commercial activated carbons in the adsorption of giant molecule is not optimal because of their disordered pore structure, low specific pore volume and significant amount of micropore, which only allows the adsorption of relatively small molecules from the gas or liquid phase. So they have low efficiency for the adsorption of compounds made of large molecules. Thus, it is essential to use new mesoporous carbon materials which have large pore volume and high surface area to enable the adsorption of bulky molecules such as proteins and vitamins. Vitamins constitute a group of compounds, which are essential for the normal growth. They contain water-soluble and fat-soluble vitamins. The well-known vitamin B12 belongs to the first group. Many diseases are related to VB12 deficiency, thus there is an increasing interest in the development of a suitable method for their separation and purification. Polymeric adsorbents (such as non-ionic macroporous crosslinked polystyrene resins) and activated carbon have been used for separation and purification of the VB12. Using ordered mesoporous silicate templates, a series of mesoporous carbon materials have been synthesized, which be called CMK-n (n = 1-5). These mesoporous carbons possess a well-ordered pore structure, high specific surface area, large pore volume and chemical inertness whichcan be used in many fields such as catalysis, hydrogen storage, separation and purification, and adsorption of bulky molecules. Very recently, Vinu et al. have prepared mesoporous carbons with various pore diameters which were synthesized at different temperatures from SBA-15 materials and studied their adsorption properties on Cytochrome C. There are many articles reporting the preparation and adsorption properties of mesoporous carbons. However, up to now, there have only been few reports on the adsorption of large biomolecules such as vitamin over mesoporous carbon molecular sieves. In this paper, we report the adsorption of VB12 on mesoporous carbons. Two important factors, physical and chemical, play major roles in the adsorption of VB12. From physical perspective, adsorbents must have large pore volume and high surface area. It is important to have a good compatibility between the size distribution of adsorbents and VB12 molecule. The effective size of VB12 molecule is 2.09 nm, which is too large to access common adsorbents. Mesoporous carbons with larger pore size and higher surface area should be developed and used for enhancing VB12 adsorption from water. From chemical perspective, it is well known that the adsorption properties are greatly influenced by the surface chemistry of the adsorbents. Chemical forces between molecular structure of VB12 and surface of mesoporous carbons can increase the adsorption ability of adsorbent. Hence, from both physical and chemical perspective, we compare adsorption properties of two different mesoporous carbons which possess different pore size distributions and surface areas, and study the influence of the surface chemistry on their ability to adsorb VB12. The replacement of liquid acids and bases by solids as catalysts in organic reactions is a requisite for better environmental preservation. While the research on solid acid catalysts was boomed by oil refining through the discovery of a large number of systems including zeolites, clays, mixed oxides, only a few solid base catalysts are yet available. The development of solid basic catalysts which could replace the liquid bases currently used in industrial processes is a major field oftoday's catalysis research. Mesoporous molecule sieves and zeolites have been shown to be potential candidates for this application due to their high thermal stability, their shape selective properties and their ability to concentrate reactants inside the pore. Several methods for the creation of basic sites in molecular sieves have been described so for. Among them, isomorphous substitution of silicon by nitrogen is common method. However, few reports on nitrogen-incorporated molecular sieves appeared. It is very difficult to avoid the collapse of molecular sieve framework when nitridation of the molecular sieves was performed in a flow of N2 or NH3 at a temperature about 800 °C. Therefore, it is not easy to obtain nitrogen-incorporated molecular sieves. In this paper, our goal is to synthesis mesoporous SiOXNY which is steadily under high temperature. The Knoevenagel condensation reaction was performed with the mesoporous SiOXNY. From the results, we can see that the nitrogen-incorporated SiOXNY samples gave different conversion. The conversion of benzaldehyde for 1200°C-40 h was higher than that of for 1100°C-20 h, due to a significant number of nitrogen content. The selectivity of this condensation product was about 100 % for all samples. We also can see that the nitrides were much more active than MgO in Knoevenagel condensation. In the past decades, mesoporous silica has attracted much research attention due to their high surface area and adjustable pore size. The wall surface of mesoporous silica can be modified with proper organic functional groups and provide accessibility for anchoring other substrates. The encapsulation of guest molecules in these hosts leads to composite materials with novel properties, which enable possible applications as materials for catalysis, adsorption, and electronic devices. The discovery of the "buckminsterfullerene"C60 molecule has attracted much attention in the whole world. The unusual geometry of this molecule may be responsible for some unique properties, and are widely used in physics, chemistry and materials science. The photochemical and photophysical properties of C60 have recently received intensive attention. Others reported that electron deficient C60 is usefulsensitizers in preparative photooxygenation reactions by the intermediacy of singlet oxygen. Singlet oxygen (1O2) is a reagent used for a variety of organic reactions. These reactions include the Ene reaction, the Diels-Alder reaction and others. In this paper, new heterogeneous catalysts that use oxygen and light to generate singlet oxygen have been prepared. We encapsulate C60 into amino-functional modified SBA-15 host. The conversion of 1-naphthol for the heterogeneous catalysts was higher than Fullerene-coated beads catalysts which be reported previously. At the same time, molecular sieves SBA-15 and silica nanotube as template are explored to synthesis CNx nanotubes. The dimension of the CNx nanotubes is defined by the selected template. The determination of trace metals such as Cu, Pb, Cd, Hg, etc, in environmental matrixes is increasingly important because of their toxic effects to animal and humans. Anodic stripping voltammetry (ASV) is one of the most sensitive techniques for the determination of trace levels of numerous ions. As it is known, the use of chemically modified electrodes (CMEs) coupled with ASV is an expanding field of investigation. There is a great variety of CMEs which has been used in the heavy metal determination as well as in speciation studies. As an example, a multi-wall carbon nanotube (MWNT) modified glassy carbon electrode was described for the simultaneous determination of trace levels of cadmium and lead by ASV and it was demonstrated its practical application for a simple, rapid and low cost determination of Cd and Pb in water samples. Based upon that, our purpose was to study the properties of the novel mesoporous carbon CMK-3 (MC) in order to explore its use in the determination of some trace metals via ASV. Therefore, here we report the utilization of the mesoporous carbon in electrodes with polyaniline, aiming the eledtrochemical detection of small amounts of Cu2+, and Pb2+ ions in aqueous solution. The performance of the mesoporous carbon electrodes was compared with similar electrodes obtained with graphite. The stripping peak currents are...
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