Mesoporous N‐rich Carbon with Single‐Ni Atoms as a Multifunctional Sulfur Host for Li‐S Batteries

Abstract

AbstractPhysicochemical confinement and catalytic conversion of lithium polysulfides (LiPSs) are crucial to suppress the shuttle effect and enhance the redox kinetics of lithium‐sulfur (Li‐S) batteries. In this study, a NH4Cl‐assisted pyrolysis strategy is developed to fabricate highly mesoporous N‐rich carbon (designed as NC(p)) featuring thin outer shells and porous inner networks, on which single‐Ni atoms are anchored to form an excellent sulfur host (designed as Ni‐NC(p)) for Li‐S batteries. During pyrolysis, the pyrolytic HCl from confined NH4Cl within ZIF‐8 will in situ etch ZIF‐8 to produce rich mesoporous in the carbonized product NC(p). The mesoporous Ni‐NC(p) enables favorable electron/ion transfer, high sulfur loading, and effective confinement of LiPSs, while the catalytic effect of single‐Ni species enhances the redox kinetics of LiPSs. As a result, the sulfur cathode based on the Ni‐NC(p) host delivers obviously improved Li‐S battery performance with high specific capacity, good rate capability, and cycling stability.