Hierarchical porous N,S‐codoped carbon material derived from halogenated polymer for battery applications

Abstract Herein, a hierarchically porous N, S‐co‐doped carbon material (named as NS‐C) has been efficiently fabricated from halogenated polymer to meet the targets of the low‐cost anode and cathode materials for Li‐based batteries. Thanks to its large N (∼5.4 at.%) and S (∼1.1 at.%) contents, large specific surface area (∼1510 m2 g–1), and beneficial pore hierarchy, the NS‐C exhibits superior bifunctional performance as anode material and S host for Li‐S cathode. The NS‐C/sulfur composite (named as S@NS‐C) delivers a large capacity of 1125 mAh g–1 at 0.1 C and maintains a capacity of 401 mAh g–1 at 5 C. A continuous long‐term use for 200 cycles at 2 C achieves large capacity retention of 80.5%. Furthermore, the NS‐C can also serve as anode material for stable Li‐ion storage with large capacity, showing very limited capacity fading for over 1000 cycles at both 0.1 and 1.0 A g–1. Moreover, considering the huge amount of halogenated polymer plastic wastes buried, burned, or discarded in the environments, our developed route of simple conversion of halogenated polymers into functional carbon materials for Li‐ion battery anode and S host for Li‐S battery cathode is advantageous for both environmental protection and Li‐based battery industry.