The Creation of a Dual-End Interface in Li─S Cathode by Anchoring Independent Metal Atoms on Graphdiyne

Conventional strategies to address sluggish polysulfide conversion and the shuttle effect have primarily focused on interactions between sulfur anions and catalytic centers, while largely neglecting the enrichment and transport of lithium ions at the cathode. Herein, we report a niobium (Nb) atomic catalyst anchored on graphdiyne (Nb-GDY) that enables a unique dual-end binding mechanism for the simultaneous regulation of polysulfide conversion and lithium-ion transport kinetics. Density functional theory calculations reveal pronounced electronic coupling between Nb─S and Li─C pairs, creating synergistic binding sites that immobilize LiPSs while lowering the energy barriers for their transformation. This mechanism is corroborated by x-ray photoelectron spectroscopy and comprehensive in situ characterizations, which demonstrate significantly accelerated electrode kinetics and efficient Li⁺ flux. Consequently, the Nb-GDY-based cathode exhibits exceptional high-rate capability and long-term durability, achieving a high capacity of 724 mAh g^-1 at 10 C and maintaining stable operation over 1200 cycles at 5 C with a low-capacity decay of 0.025% per cycle. Our research ingeniously combines dual ends binding, activating the synergistic interaction between atoms and the substrate, providing a new concept for the management of multi-species transport for high energy density Li-S batteries.