2D g-GaN as Interphase Anode Layer in Mg Battery for Capturing Passivation Species (MgO, Mg(OH) 2, Mg(CO 3 ) – A First-Principles Study

Abstract The first principles study has been carried out to analyze the performance of the 2D graphene-Gallium Nitride (g-GaN) as interphase material at the magnesium electrode (g-GaN@Mg) for capturing the passivation species such as magnesium oxide (MgO), magnesium hydroxide (Mg(OH)₂), and magnesium carbonate (MgCO₃) in Rechargeable Magnesium (RMB) batteries. The current work shows that the calculated interphase binding energy (Eb) between the Mg and g-GaN layers are strong. Ab initio molecular dynamics (AIMD) simulation confirms the thermal stability of the g-GaN@Mg at 500 K. The excellent anodic properties of the g-GaN@Mg surface has been confirmed from adsorption energy and diffusivity of single Mg atom values, -2.64 eV and 10⁻ ³ cm²/s respectively. Interaction of passivation species MgO, (Mg(OH)₂) and (MgCO₃) with g-GaN@Mg surface demonstrates a weakening of the Mg-O and Mg-C bond distance. The findings mentioned above suggest that the g-GaN@Mg surface is a potential protective layer against the passivation species for Mg batteries.