Hydrogen storage performance of methyl-substituted mesoporous silica with tailored textural characteristics

The present study reports a systematic analysis of morphology and hydrogen sorption capacity of mesoporous organic-inorganic silica prepared by varying the silica synthesis parameters. Cationic surfactants of different chain lengths and different proportions of functionalised precursors were introduced in the synthesis mixture. Improved hydrogen storage properties have been obtained, already below 20 bar, reaching a maximum storage capacity around 4.75 wt% at 80 bar. The textural characteristics were analysed by nitrogen sorption and small angle X-ray scattering, and the thermal stability has been characterized by thermogravimetric analysis. The materials show specific surface area between 400 and 700 m2/g and a weakly ordered mesoporosity induced by the short chain surfactant template.