In Situ Alkali Metal Exfoliation-Coupled Dilute CO₂ Electrolysis to Synthesize Interlayer-Expanded Graphite for...

Converting CO₂ into ideal carbon anode materials for fast lithium storage brings a win-win prospect toward energy and environment domains. Here, we propose a one-pot stepwise strategy to synthesize expanded d-spacing (up to 0.405 nm) graphite by direct electroreduction of dilute CO₂ (e.g., 10 vol%, close to practical industrial flue gas) in molten electrolytes, where the as-formed CO₂-derived graphite with pristine interlayer spacing was enlarged by the sequential in situ exfoliation of alkali metals. Owing to the predominant thermodynamic tendency, dilute CO₂ was preferentially electro-transformed into carbon materials at a promising current density of 100 mA/cm². Serving as a LIBs anode, the obtained graphite with expanded d-spacing exhibited a relatively high lithium storage capacity (152 mAh/g) at a high charge/discharge current density of 2000 mA/g, fivefold compared with that of commercial graphite, reaching a retention rate of 91% after 500 cycles. This work provides insights on rational design of high-rate lithium storage anode for next-generation LIBs industry with a lower carbon footprint.