Engineering Oversaturated Fe‐N₅ Multifunctional Catalytic Sites for Durable Lithium‐Sulfur Batteries

Abstract

Lithium‐sulfur (Li‐S) batteries are regarded as a promising next‐generation system for advanced energy storage owing to a high theoretical energy density of 2600 Wh kg−1. However, the practical implementation of Li‐S batteries has been thwarted by the detrimental shuttling behavior of polysulfides, and the sluggish kinetics in electrochemical processes. Herein, a novel single atom (SA) catalyst with oversaturated Fe‐N5 coordination structure (Fe‐N5‐C) is precisely synthesized by an absorption–pyrolysis strategy and introduced as an effective sulfur host material. The experimental characterizations and theoretical calculations reveal synergism between atomically dispersed Fe‐N5 active sites and the unique carbon support. The results exhibit that the sulfur composite cathode built on the Fe‐N5‐C can not only adsorb polysulfides via chemical interaction, but also boost the redox reaction kinetics, thus mitigating the shuttle effect. Meanwhile, the robust three‐dimensional nitrogen doped carbon nanofiber with large surface area, and high porosity enables strong physical confinement and fast electron/ion transfer process. Attributed to such unique features, Li‐S batteries with S/Fe‐N5‐C composite cathode realize outstanding cyclability and rate capability, as well as high areal capacities under raised sulfur loading, which demonstrates great potential in developing advanced Li‐S batteries.

Mesoporous N‐rich Carbon with Single‐Ni Atoms as a Multifunctional Sulfur Host for Li‐S Batteries

“…[2,5,17] Among them, single-atom catalysts have aroused great interest due to their unique properties. [3,7,[32][33][34][35][36][37][38][39] For example, single-metal atoms (e.g., Fe, Co and Ni) on NC supports are highly effective for accelerating the kinetic conversion of LiPSs and suppressing the undesirable shuttle effect. [3,7,33] Based on the above points, constructing a multifunctional sulfur host by integrating single-metal atoms capable of converting LiPSs into an advanced NC framework might achieve further advancement in Li-S batteries.…”

Engineering Fe and V Coordinated Bimetallic Oxide Nanocatalyst Enables Enhanced Polysulfides Mediation for High Energy Density Li‐S Battery

“…For the XPS results, it can be rationally deduced that the electron clouds of S-group are pulled toward Fe and V atoms in FVO-Li 2 S 6 , implying the intense interaction between FVO and Li 2 S 6 . [34] The Hirshfeld charge distributions based on DFT calculations are carried out to theoretically verify the conclusion. Figure 2j shows the Hirshfeld charge levels of Fe, V, and S atoms in FVO, Li 2 S 6 , and FVO-Li 2 S 6 , respectively.…”

Bridging Trans-Scale Electrode Engineering for Mass CO2 Electrolysis

“…The regulation of catalyst composition contributes to the adsorption of intermediates, which further tunes the selectivity of electrochemical reactions. 63,64 Supported by the experimental and DFT calculation results, Zhu et al proposed the mechanism of reducing CO 2 to CO on nitrogen-doped MoS 2 and nitrogen-doped carbon point catalysts (Figure 5b). 65 First, CO 2 forms *COOH intermediates by adsorbing a proton− electron pair onto Mo atoms on the catalyst surface.…”