The Synthesis And Applications Of Mesoporous Materials

Since the use of CTAB as the surfactant to synthesize the M41S mesoporous materials with ordered structure has been reported, mesoporous materials attracted more and more attentions because of the uniform pore size, high surface area and pore volume, adjustable pore size, modifiable properties, and various morphologie/structure, etc. During the 10 years, the research content of mesoporous materials has been developed. At present, the research focus on the functional mordification, the synthesis of the non-silica materials and the design of application. Mesoporous materials are widely used in adsorption, separation, catalysis, biopharmaceutics, sensor, and optics/electricity/magnetism, etc.Organic-inorganic self-assembly takes a key role in the synthesis of mesoporous materials. The interaction of self-assembly mainly includes: electrostatic force, van der waals force, hydrogen-bond, and coordination interaction. Under the investigation on the self-assembly process, resachers proposed two possible mechanisms: liquid crystal template and cooperative formation mechanism, that is beneficial to design new mesoporous materials. They considered that: the surfactant, inorganic species, and solvent determined the synthesis of the mesoprous materials. In this paper, according to the self-assembly mechanism, we designed and synthesized new mesoporous materials, and studied their application on drug delivery. Beside that, we also did some study about using mesoporous carbon materials on hydrogen storage and capacitor.Polymer-mesoporous silica nanoparticles have been synthesized by a dual-template technology. Cationic polymer, quaternized poly[bis(2-chloroethyl)ether-alt-1,3-bis[3-(dimethylamino)propyl]urea] (PEPU), and anionic surfactant sodium dodecyl sulfate (SDS) were used to form a homogeneous comicelle system to induce mesoporous silica spherical nanoparticles with diameters of 50-180 nm. The formation mechanism was studied by transmission electron microscopy (TEM), which suggested that PEPU played a cotemplate role in the synthesis process, and no mesoporous structure was generated without it. After removing the anionic surfactant, SDS, by an ion-exchange method, the cationic polymer-mesoporous silica nanoparticles were obtained. Using the materials as the host and ibuprofen (IBU)/captopril (CapH2) as the model drugs, the system revealed well-sustained release profiles. To validate the biocompatibility of the polymer-silica material, the sample was incubated with ratmesangial (HBZT-1) cells, and MTTASSAY was used to detect the cell viability . After being incubated with the sample for 48 h, the cell viability remained 96.96%. The polymer-silica showed almost no cytotoxicity to HBZT-1 cells, indicating that the sample had good compatibility and great potential for use in biopharmaceutics.A new mixed surfactant system with alkyl carboxylic acid(lauric acid, myristic acid, palmitic acid, and stearic acid) as anionic surfactant and cationic polymer PEPU as co-template was used to synthesize mesoporous silica materials with various morphologies and structures, including flakes, regular spheres, small particles, and tube/spheres morpholoy with wormlike or Im3m mesoporous structures. Depending on the chain lengths of alkyl carboxylic acids, the pore sizes of these mesoporous materials could be controlled from 3.0 to 5.0 nm. The interaction betweem the anion surfactant and the cationic polymer was very important in the formation of the mesopore. Zeta potential was used to evaluate the interaction between the anionic surfactants and the cationic co-template. The synthesis of the mesoporous was determined by many factors, such as: the structure, charge density and amount of cationic polymer, the chain length of surfactants, and the molar ratio, the interaction of the surfactant/polymer. The oppositely charged surfactant/polymer system is expected to extend to other surfactants and polymers to synthesize mesoporous materials with more special morphologies and structures. The different pore sizes, the various morphologies and structures make these materials possess potential applications in catalysis, separation, adsorption and control release etc.SBA-15 was used as the hard template, and two strategies were used to synthesize the carbon mesoporous materials. In the first method, aromatic polymer was used as the carbon course, adopting dissolve impregnation, under N2 atmosphere/vacuum to generate carbon materials. The second method was based on the chemical vapor deposition (CVD) of ferrocene in SBA-15, which was carbonized to produce carbon materials. The structures of these materials are analogous to CNT or CNF. As we know, CNT and CNF is good candidate for hydrogen storage. So we try to use these materials for storing hydrogen, hoping to get higher storage ability. With the highest surface area and pore volume, F1 (1249m2/g and 1.34 cm3/g) possess the large storage ability(5.57 wt%, H2, 77K 90bar and 6.06 wt%, CH4, 298K 70bar). We also studied the correlation between the pore characterize and the storage ability. The miroporous volume is the dominant factor of the hydrogen storage.Mesoporous carbon materials with different pore structures, including p6mm, Im 3 m and Ia 3 d (CS-15, CK-5, and CK-6) were synthesized by using different mesoporous silica as the template. Aromatic polymer was used as the carbon source. The result samples possessed a certain graphitization degree and low resistant (about 1?). With more open framework structure, the 3D structure and large pore size carbon materials possessed more accessibility for the electrolyte penetrating into the carbon pores( Im 3 m> Ia 3 d> p6mm). CK-5 possessed the highest capacitance and the stability according to the differnent sweep rate. From the results of CV and EIR, we can find that the electrochemistry activity for CK-5 was the closest to the ideal capacitor.