Electrochemical Conversion of CO 2 via Molten Salt Electrolysis to Produce Hard Carbon Materials for Sodium-Ion Battery

High Resolution Image Download MS PowerPoint Slide The conversion of CO 2 into valuable carbon materials is essential for establishing a circular economy. This study syntheses hard carbon materials from CO 2 using high-temperature molten salt electrolysis and explores their use as anodes in sodium-ion batteries. CO 2 gases are absorbed as carbonate ions in molten salts and then electrochemically decomposed into solid carbon. When electrolysis was conducted at 600 °C in molten LiCl-KCl containing Li 2 CO 3, the generated carbon was amorphous and nongraphitizable, as determined by XRD analysis and Raman spectroscopy. The obtained carbons before and after heat treatments at 900–1800 °C were employed as the anode materials in two-electrode cells with metallic sodium counter electrodes and 1 M NaPF 6 /EC-DMC electrolyte. for sodium ion battery. The carbon treated at 900 °C showed the highest capacity, exceeding that of commercial hard carbon materials. These results demonstrate the potential of CO 2 reduction and technologies for converting CO 2 into valuable carbon materials for energy storage devices.