Microstructure engineering in sulfuretted coal tar pitch by varying the Cross-Link state for enhanced sodium storage.

Sulfur (S) is an efficient dopant to enhance the sodium storage of carbon, yet the conventional in-situ/post treatments cause unstable S configuration or lower S content, and hence unsatisfied electrochemical performance. Herein, we investigate sulfurization at various cross-link state of coal tar pitch (CTP) (pristine, coke, and carbonized states), and the microstructure of the products (SCTP). Experimental and calculational results reveal that introducing S in the coke state of CTP is essential for achieving abundant and stable C-S-C bonds between carbon layers.

Highly efficient utilization of sodium storage sites for MOF-derived carbon by rapid carbonization.

Rapid carbonization within only 10 min achieves the balance of sodium storage sites and electronic conductivity for MOF-derived carbon, delivering excellent sodium storage properties. This work supplies a novel and environment-friendly method to treat MOF-derived materials in the field of electrochemistry.

Directional modification of oxygen functional groups by N heteroatoms on soft/hard carbons for sodium storage.

Different oxygen functionalization processes occur for N-doped soft carbon (N-SC) and hard carbon (N-HC), and there may be a competitive relationship between the formation of pyridinic-N and CO groups. For N-SC, abundant CO groups and defects bring excellent Na storage performance and cycling stability, especially at high current densities.