Effects of P‐doping on CO₂‐Derived Porous Carbon for the Cathode of Lithium‐Sulfur Batteries

To address the sluggish redox kinetics and the polysulfide shuttle effect in lithium‐sulfur (Li–S) batteries, phosphorus‐doped CO 2 ‐derived carbon (PCDC) was developed to improve their electrochemical performance. The carbon scaffold was derived from CO 2 reduction through sodium borohydride (NaBH 4 ), enabling the simultaneous incorporation of boron and oxygen. This eco‐friendly strategy converts CO 2 into a hierarchically porous structure with the phosphoric acid treatment. The resulting PCDC exhibited a large surface area and pore volume, enabling effective sulfur loading and rapid lithium‐ion transport. Structural analyses confirmed the presence of both B and P within the carbon matrix, with B contributing to enhanced electrical conductivity and P forming catalytically active configurations such as C 3 PO and C 2 PO 2 . Electrochemical testing revealed that PCDC accelerates polysulfide redox reactions, reduces charge transfer resistance, facilitates Li 2 S nucleation, and outperforms the CO 2 ‐derived carbon (CDC) without phosphorus doping. It delivered a capacity of 800 mAh g −1 for 100 cycles at 0.2C and showed around 600 mAh g −1 after 100 cycles at 0.5C. This multi‐heteroatom doping approach offers a practical route to high‐efficient Li–S batteries.