Designing and mapping cascade catalysis pathway for balanced polysulfide conversion in Li-S batteries
Leyuan Zhang1,2, Dongfang Cheng3, Pu Zhang4
1Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.
Nature Communications
|July 1, 2026
Summary
Lithium-sulfur batteries face challenges from slow sulfur reduction. This study reveals a cascade catalysis pathway on Fe,N,S-codoped graphene that balances intermediate conversion, suppressing the shuttle effect for improved battery stability.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- Lithium-sulfur batteries are limited by the slow 16-electron sulfur reduction reaction.
- Complex polysulfide intermediates (Li2Sn) cause unbalanced conversion and the shuttle effect.
Purpose of the Study:
- Elucidate the complete cascade pathway of sulfur reduction on a model catalyst.
- Mechanistically understand how cascade catalysis regulates polysulfide conversion.
Main Methods:
- Density Functional Theory (DFT) calculations.
- Kinetic analysis.
- Operando Raman spectroscopy.
Main Results:
- Fe sites activate long-chain polysulfides; N,S-C sites convert Li2S4 to Li2S2/Li2S.
- Synergistic catalysis balances sulfur reduction kinetics and reduces polysulfide accumulation.
- Cascade catalysis pathway confirmed to modulate intermediates and enable balanced conversion.
Conclusions:
- Cascade catalysis is a mechanism-driven strategy for designing lithium-sulfur battery electrodes.
- Pathway regulation via synergistic catalysis suppresses polysulfide shuttling.
- Enhanced cycling stability achieved through balanced polysulfide conversion.
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