Zn-CO₂ Batteries with 2D MoS₂ Catalysts for Sustainable Energy Storage

The rising levels of atmospheric CO₂ demand urgent action toward carbon-neutral energy solutions. Metal-CO₂ batteries uniquely combine the CO₂ reduction (CO₂RR) with energy storage, enabling the dual function of carbon capture and electricity generation within a single system. Among these, Zn-CO₂ batteries stand out due to the abundance, low cost, safety, and environmental compatibility of zinc. This work presents a novel Zn-CO₂ battery architecture that enables spontaneous electrochemical discharge in an aqueous NaCl electrolyte, eliminating the need for complex and high-cost components. It employs two-dimensional (2D) MoS₂ as a bifunctional electrocatalyst to facilitate the CO₂RR and battery rechargeability. The MoS₂@carbon cathode exhibited a superior discharge capacity of approximately 50% higher than the bare carbon cathode and a lower overpotential (0.25 V), delivering a notably high energy density of ∼1200 Wh kg^-1 based on the total mass of the cathode. Unlike conventional Zn-CO₂ systems restricted to nonaqueous media, this design achieves stable cycling under ambient conditions through reversible Zn carbonate chemistry, while MoS₂ catalysis lowers overpotential and boosts capacity and durability, yielding a highly efficient, cost-effective platform for carbon-neutral energy storage.