Highly efficient sulfur cathode built from biomass of hierarchical porous carbon for aqueous Cu–S batteries

Abstract

Rechargeable aqueous metal–sulfur batteries have received considerable attention due to their low cost, reliable security, and environmental friendliness. However, their poor cycle performance impedes their development. Herein, a nitrogen-doped hierarchical porous carbon material prepared from pomegranate peel was used to host sulfur molecules and then served as cathode material for Cu–S battery. The material showed a high specific surface area of 1167.16 m² g⁻¹, due to its hierarchical porous structure, and showed good electronic conductivity. Based on these advantages, the sulfur@nitrogen-doped hierarchical porous carbon cathode displayed excellent electrochemical properties with a high specific capacity of 1911.8 mA h g⁻¹ at 2 A g⁻¹ and outstanding capacity retention of up to 93%, and hence shows great promise as a practical cathode material of Cu–S batteries.