Bottom-Up Synthesis of Advanced Carbonaceous Anode Materials Containing Sulfur for Na-Ion Batteries

The fabrication of sulfur-containing carbonaceous anode materials (CS) that show exceptional activity as anode material in Na-ions batteries is reported. To do so, a general and straightforward bottom-up synthesis of CS materials with precise control over the sulfur content and functionality is introduced. The new synthetic path combined with a detailed structural analysis and electrochemical studies provide correlations between i) the sulfur content and chemical species and ii) the structural, electronic, and electrochemical performance of the associated materials. As a result, the new CS substances demonstrate excellent activity as Na-ion battery anode materials, reaching capacity values above 500 mAh g⁻¹ at a current density of 0.1 A g⁻¹, as well as high reversible sodium storage capabilities and excellent cycling durability. The results reveal the underlying working principles of carbonaceous materials, alongside the storage mechanism of the Na⁺ ions in these advanced sodium-ion battery anode materials and provide a new avenue for their practical realization.