Mechanisms of adsorbing hydrogen gas on metal decorated graphene

Hydrogen is a key player in global strategies to reduce greenhouse gas emissions. In order make hydrogen widely used fuel, we require more efficient methods of storing it than the current standard pressurized cylinders. An alternative method adsorb ${\mathrm{H}}_{2}$ material and avoid use high pressures. Among many potential materials, layered materials such as graphene present practical advantage they are lightweight. However, other 2D typically bind too weakly store at typical operating conditions fuel cell, meaning that pressure would still be required. Modifying material, for example by decorating with adatoms, can strengthen adsorption energy molecules, but underlying mechanisms not well understood. this work, systematically screen alkali alkaline-earth metal decorated sheets static thermodynamic from first principles focus on binding. We show there three each leads distinctly different structures. The described weak van der Waals physisorption, adatom facilitated polarization, Kubas adsorption. these mechanisms, find easily perturbed an external electric field, providing way tune This work foundational builds our understanding under idealized conditions.