“…Porous metal oxides (NiO, ZnO, Al 2 O 3 , MgO, and TiO 2 ) have recently been investigated for hydrogen storage [19]. The important characteristics of TiO 2 , such as non-toxicity, chemical inertness, low cost, and environmental friendliness, make them suitable for use in a variety of applications such as paints, fuel cells, solar cells, gas sensors, hydrogen storage, antimicrobial materials, and photocatalysis [20][21][22]. There are materials that store hydrogen as hydrides and others that adsorb hydrogen molecules onto their surfaces.…”