biostudies-literatureUnknown2(10)Jin JSluggish sulfur reduction reaction (SRR) kinetics remains a formidable challenge in Li-S electrochemistry. In this sense, the rational design of single-atom species has become a burgeoning practice to expedite sulfur redox, where the underlying catalytic mechanism otherwise remains elusive. Herein, a class of metal single-atom modified porous carbon nanofiber films (MSA PCNFs, M = Fe, Co, or Ni), fabricated via a generic synthetic strategy, as mediators to boost SRR kinetics is reported. Throughout electrokinetic measurement and operando instrumental probing, NiSA PCNF is evidenced to harness the catalytic superiority toward the rate-determining step (i.e., liquid-solid conversion) of the SRR process. Density functional theory (DFT) simulations further reveal that the catalytic features ofSmall science2200059https://www.ebi.ac.uk/biostudies/studies/S-EPMC11935855biostudies-literatureDemystifying Activity Origin of M-N-C Single-Atomic Mediators Toward Expedited Rate-Determining Step in Li-S Electrochemistry.PMC11935855Wang MHuang TDing YWang PCai JYan TZhang LShi ZJin JSun ZSun JfalseDemystifying Activity Origin of M-N-C Single-Atomic Mediators Toward Expedited Rate-Determining Step in Li-S Electrochemistry.Sluggish sulfur reduction reaction (SRR) kinetics remains a formidable challenge in Li-S electrochemistry. In this sense, the rational design of single-atom species has become a burgeoning practice to expedite sulfur redox, where the underlying catalytic mechanism otherwise remains elusive. Herein, a class of metal single-atom modified porous carbon nanofiber films (MSA PCNFs, M = Fe, Co, or Ni), fabricated via a generic synthetic strategy, as mediators to boost SRR kinetics is reported. Throughout electrokinetic measurement and operando instrumental probing, NiSA PCNF is evidenced to harness the catalytic superiority toward the rate-determining step (i.e., liquid-solid conversion) of the SRR process. Density functional theory (DFT) simulations further reveal that the catalytic features of2022-01-01T00:00:00Z2022 Oct2025-07-09T03:05:04.259Z2025-07-09T03:05:04.259ZS-EPMC119358554021270610.1002/smsc.202200059