Thermally induced evolution of pore geometry and its influence on hydrogen adsorption: A molecular dynamics approach

This article investigates the hydrogen storage capabilities of amorphous silicon dioxide ( a- SiO₂) and its structural characteristics that influence hydrogen adsorption. It emphasizes the advantages of a -SiO₂, such as its high surface area, low cost, and thermal stability, making it a promising candidate for large-scale hydrogen storage applications. The research employs molecular dynamics simulations to explore how temperature-dependent variations in pore size and structure affect hydrogen sorption efficiency. The findings reveal that slower cooling rates significantly increase pore size, enhancing hydrogen storage capacity, with optimal conditions yielding a maximum gravimetric density of 2.07 wt.% at 100 MPa. Despite its potential, the study notes that the hydrogen storage capacity of a -SiO₂ remains limited under standard room temperature conditions due to transformations of adsorbed hydrogen and structural limitations. The insights gained from this study are vital for future experimental research aimed at improving hydrogen storage in porous materials.