Disordered 3 D Multi‐layer Graphene Anode Material from CO 2 for Sodium‐Ion Batteries

We report the application of disordered 3 D multi‐layer graphene, synthesized directly from CO 2 gas through a reaction with Li at 550 °C, as an anode for Na‐ion batteries (SIBs) toward a sustainable and greener future. The material exhibited a reversible capacity of ∼190 mA h g −1 with a Coulombic efficiency of 98.5 % at a current density of 15 mA g −1 . The discharge capacity at higher potentials (>0.2 V vs. Na/Na + ) is ascribed to Na‐ion adsorption at defect sites, whereas the capacity at low potentials (<0.2 V) is ascribed to intercalation between graphene sheets through electrochemical characterization, Raman spectroscopy, and small‐angle X‐ray scattering experiments. The disordered multi‐layer graphene electrode demonstrated a great rate capability and cyclability. This novel approach to synthesize disordered 3 D multi‐layer graphene from CO 2 gas makes it attractive not only as an anode material for SIBs but also to mitigate CO 2 emission.