Recent Advances in Cathode Materials for Room-Temperature Sodium-Sulfur Batteries.

Room-temperature sodium-sulfur (RT-Na/S) batteries hold great promise to meet the requirements of large-scale energy storage due to their high theoretical energy density, low material cost, resource abundance, and environmental benignity. However, the poor cycle performance and low utilization of active sulfur greatly hinder their practical application. As the essential part directly related to the battery performance, the S-based cathode has attracted tremendous research interests in recent years. This review highlights recent progress in cathode materials for RT-Na/S batteries. Particularly, basic insights into the Na/S reaction mechanism are presented and representative works on S-based cathode materials are systematically summarized. The remaining challenges and developing trends of RT-Na/S batteries are also discussed. We hope this review can shed light on the field of next-generation metal-sulfur batteries.