Bioinspired Fe/Mn Dual-Atom Catalysts with Mesoporous Channels for Rapid Polysulfide Redox Kinetics and Stable Lithium-Sulfur Batteries.

Abstract

The sluggish sulfur redox kinetics and severe polysulfide shuttling significantly hinder the practical performance of lithium-sulfur batteries (LSBs). While single-atom catalysts (SACs) have shown promise in capturing and catalyzing sulfur species, their catalytic activity still requires further enhancement for real-world applications. Inspired by natural superoxide dismutase, which utilizes dual-atom catalytic sites and a synergistic mechanism for rapid substrate conversion, we developed a bioinspired Fe/Mn dual-atom catalyst (FeMn-DAC) anchored on nanochannel-decorated carbon to improve sulfur redox kinetics and enable high-performance LSBs. Experimental results reveal that LSBs equipped with FeMn-DACs electrocatalyst exhibit the fastest nucleation (369.3 mAh g-1) and dissolution (226.3 mAh g-1) kinetics of Li2S. The battery demonstrates outstanding rate performance, delivering a reversible capacity of 670 mAh g-1 at 2.0 C, coupled with an ultralow capacity decay rate of 0.09% over 500 cycles. Even under high sulfur loadings of 2.79 mg cm-2 and 3.67 mg cm-2, the FeMn-DACs-based cathodes achieve excellent area capacities of 2.06 mAh cm-2 and 2.69 mAh cm-2, respectively. This work provides a new perspective for designing advanced dual-atom catalysts tailored for LSBs.