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The reversible hydrogen desorption–absorption of γ–Mg(BH 4 ) 2 ball milled with MoO 3 and TiO 2 has been investigated. No mechanochemical interaction between γ–Mg(BH 4 ) 2 and TiO 2 was observed while for the 1:1 M ratio with MoO 3 , MoB 2 was formed. There was little difference in the properties of γ–Mg(BH 4 ) 2 and γ–Mg(BH 4 ) 2 ball–milled with 0.02 mol percent TiO 2 and MoO 3 . However, mixing in the same ratio γ–Mg(BH 4 ) 2 with TiO 2 and MoO 3 that had previously been subjected to high energy milling provided significant effects. For these materials, the DSC peaks appeared broader and were shifted to slightly lower temperatures, while the TPD peaks were decreased by ca. 20 °C, as compared to the pure γ–Mg(BH 4 ) 2 . Faster hydrogen desorption kinetics was observed for the γ–Mg(BH 4 ) 2 –MoO 3 mixture. The reversible hydrogen storage capacity of γ–Mg(BH 4 ) 2 –TiO 2 at 271 °C was found to be 2.4 wt% H 2 in the first cycle.

Novel hexagonal Periodic Mesoporous Organosilicas (PMOs) and Disordered Mesoporous Organosilicas (DMOs) were synthesized by hydrolysis of 1,4-bis(trialkoxylsilyl) benzene precursor in alkaline aqueous solutions of different alkyl-trimethyl ammonium cations and evaluated for their hydrogen storage capacity. The PMO materials exhibit regular hexagonal pore arrangement and specific surface area between 640 and 782 m2 g−1 whereas the DMO materials have specific surface area that lies between 650 and 910 m2 g−1. The storage capacity of the materials is discussed in terms of number of molecules per surface unit. The materials exhibit a reversible hydrogen excess surface adsorption capacity up to 2.10 wt% at 6 MPa and 77 K. DFT calculations were performed to define the binding strength of hydrogen with the pore walls indicated an interaction energy value of −0.55 Kcal mol−1, higher than the interaction energy value of hydrogen with a single benzene or a benzene incorporated in the IRMOR-1 walls. Grand Canonical Monte Carlo (GCMC) simulations showed that no hydrogen molecule can be inserted inside the wall structure of the materials.