The development of sustainable and environmentally friendly rechargeable battery technology is one of the prominent areas of research for future energy demand. Among all the existing technologies Li based ones (Li-ion batteries) are the front runners, but the limited abundance of lithium, environmental hazards and, more importantly, their thermal instability severely limits the use of these batteries in the future. As analternative to the Li-based technology, in the recent past, Aluminium based rechargeable batteries (AIBs) are gaining more attention due to the unprecedented qualities of Al metal as an anode in the AIBs. However, commercialization of AIB requires limited volume expansion of the cathode materials after intercalation (charge-carrying ion in AIBs), lower activation barrier, high theoretical specific capacity (TSC), cyclic durability and thermodynamical stability. To understand the mechanism of AIBs and to design efficient cathode materials for this battery technology, here we employed multipronged first principles computational approaches and explored various carbon-based cathode materials. We reveal that compared to the traditional natural allotropes of carbon like graphene, various forms of graphite, non-natural allotropes such as members of graphyne family (graphdiyne, α, β, γ-graphynes, etc.) with large porous structure shows superior performance in terms of TSC(∼186 mAh/g for graphdiyne, α, γ-graphyne compared to 65 mAh/g for graphite), low diffusion energy barriers (∼0.05-0.08 eV), shows improved conductivity and excellent thermodynamical stability (in the pristine form and after adsorption) and more importantly, they resolve the major roadblock for AIBs, degradation of cathode materials due to volume expansion (as α-graphyne shows only ∼186 % expansion compared to ∼280 % of graphite) after intercalation with bulky electrolyte anion. With these promising battery- related matrices, graphyne family members are suitable as cathode materials for AIBs.



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