Breaking Coordination Symmetry: A Structural Design Strategy for Accelerating Polysulfides Conversion in Lithium‐Sulfur Batteries

Lithium‐sulfur (Li‐S) batteries are regarded as promising candidates for next‐generation energy storage systems, it is pivotal to expedite reaction kinetics and inhibit polysulfides shuttle effect for their practical application. Herein, an unsymmetric coordination strategy has been proposed to enhance the intrinsic catalytic activity and polarity of molecular catalysts, as exemplified by a nickel N‐confused porphyrin complex (NiNCP) featuring an unsymmetric metal coordination environment. The molecular catalysts are uniformly loaded on the surface of graphene oxide nanosheets (NiNCP@GO) for the modification of polypropylene (PP) separators. The formation of metal‐carbene bonds in NiNCP induces symmetry breaking of the metal porphyrin molecule, which optimizes the electronic structure of the Ni center, thus exhibiting superior catalytic activity for polysulfides conversion compared to its symmetrical metal porphyrin counterparts. The functionalized separator enables sulfur cathodes to achieve a high discharge capacity of 1460 mAh g −1 at 0.1C, and the average capacity decay is only 0.019% per cycle over 1000 cycles at 1.0C. Moreover, the impressive areal capacity of 6.02 mAh cm −2 and volumetric capacity of 926 mAh cm −3 are achieved in a high sulfur content of 90 wt.% at 0.2C. This work expands the application of symmetry‐broken molecular catalysts in Li‐S batteries.