Quest for carbon and vanadium oxide based rechargeable magnesium-ion batteries

Rechargeable magnesium ion batteries are potential candidates to replace the lithium ion batteries due to their high volumetric energy density, dendrite free cycling, and low costs. In present work, we have critically reviewed the recent advances made in the field of cathode materials development to achieve the high reversible capacities and working potentials. In first part, carbon-based cathodes such as fluorine-doped graphene nanosheets and graphite fluoride (CF0.8) are discussed in terms of compatibilities of positive electrode materials and electrolyte solutions for rechargeable magnesium-ion batteries. Whereas, the second part of this review focuses on crystal structure of vanadium oxide and its capability to accommodate the Mg2+ ions. Likewise, electrochemical performance of selected vanadium oxide based cathodes including VO2 (B), FeVO4.0.9H2O, Mo2.5+yVO9+δ, RFC/V2O5 and V2O5/Graphene composite, are discussed at different temperatures. To support the future research on magnesium ion batteries, particularly positive electrode material developments, several innovative research directions are proposed.