Graphene/hBN Heterostructures as High-Capacity Cathodes with High Voltage for Next-Generation Aluminum Batteries

Abstract

The field of Al batteries immensely demands the development of highly efficient cathode materials which can provide large storage capacities along with maintaining a constant high voltage. In this work, using the first-principles calculations, we have proposed the graphene/hexagonal boron nitride heterostructure (G/hBN) as a suitable cathode material for Al batteries. We have systematically investigated the binding, electronic, and electrochemical properties for the AlCl4-adsorbed/intercalated G/hBN heterostructure in various possibilities, and a necessary comparison has also been executed with the pristine monolayer of graphene and hBN. It is observed that the binding strength of AlCl4 has significantly improved on the outer surfaces of graphene and hBN and in interlayer spaces of the G/hBN heterostructure compared to monolayer hBN, besides maintaining a similar strong binding as that of monolayer graphene. The lower diffusion barrier (0.01 eV) ensures a faster charge/discharge rate in the G/hBN heterost...