Preparation of Mesoporous Silica and Its Applications in Hydrogen Storage Materials.

摘要

The present study investigated the synthesis of mesoporous silica nanospheres (MSNs) and the application of mesoporous silica in hydrogen storage applications.;MSNs with particle sizes ranging from ca. 25 to 150 nm are synthesized via sol-gel chemistry with 80 °C isothermal water bath. Initial pH values of the reactant solution were used as control parameters to tune both the particles and pores size of the products. We modified the syntheses conditions and synthesized MSNs using a microwave-assisted heating approach. The introduction of microwave-assisted heating results in better crystallized MSNs.;After enhanced hydrogen release properties of pretreated AB were study, some AB/MSN nanocomposites were prepared and the hydrogen release properties of these composites were evaluated. It was found that the AB/MSN nanocomposites had faster hydrogen release kinetics. A critical loading level of ca.0.15 (weigh ratio of AB to MSNs) was found. When the loading level of the nanocomposites is below the critical level, the first two moles hydrogen would be released simultaneously from AB at temperature below 90 °C. Additional, the critical loading level still exists in the AB/mesoporous silica nanocomposite materials of different mesopore sizes, and their critical loading level is affected by the total surface area of the mesopores.