Adsorption of molecular hydrogen on Be3Al2(SiO3)6-beryl: theoretical insights for catalysis, hydrogen storage, gas separation, sensing, and environmental applications

Abstract

Employing a combination of Density Functional Theory (DFT) calculations and Molecular Dynamics (MD) simulations, the adsorption of molecular hydrogen (H₂) on Be₃Al₂(SiO₃)₆-beryl, a prominent silicate mineral, has been studied. The crystal structure of beryl, which consists of interconnected tetrahedral and octahedral sites, provides a fascinating framework for comprehending H₂ adsorption behavior. Initial investigation of the interaction between H₂ molecules and the beryl surface employed DFT calculations. We identified favorable adsorption sites and gained insight into the binding mechanism through extensive structural optimizations and energy calculations. H₂ molecules preferentially adsorb on the exposed oxygen atoms surrounding the octahedral sites, producing weak van der Waals interactions with the beryl surface, according to our findings. To further investigate the dynamic aspects of H₂ adsorption, MD simulations employing a suitable force field were conducted. To precisely represent interatomic interactions within the Be₃Al₂(SiO₃)₆-beryl–H₂ system, the force field parameters were meticulously parameterized. By subjecting the system to a variety of temperatures, we were able to obtain valuable information about the stability, diffusion, and desorption kinetics of H₂ molecules within the beryl structure. The comprehensive understanding of the H₂ adsorption phenomenon on Be₃Al₂(SiO₃)₆-beryl is provided by the combined DFT and MD investigations. The results elucidate the mechanisms underlying H₂ binding, highlighting the role of surface oxygen atoms and the effect of temperature on H₂ dynamics. This research contributes to a fundamental understanding of hydrogen storage and release in beryllium-based silicates and provides valuable guidance for the design and optimization of materials for hydrogen storage, catalysis, gas separation, sensing and environmental applications.