Evolution of Stabilized 1T‐MoS₂ by Atomic‐Interface Engineering of 2H‐MoS₂/Fe−N_<i>x</i> towards Enhanced Sodium Ion Storage

Abstract

Metallic conductive 1T phase molybdenum sulfide (MoS₂ ) has been identified as promising anode for sodium ion (Na⁺ ) batteries, but its metastable feature makes it difficult to obtain and its restacking during the charge/discharge processing result in part capacity reversibility. Herein, a synergetic effect of atomic-interface engineering is employed for constructing 2H-MoS₂ layers assembled on single atomically dispersed Fe-N-C (SA Fe-N-C) anode material that boosts its reversible capacity. The work-function-driven-electron transfer occurs from SA Fe-N-C to 2H-MoS₂ via the Fe-S bonds, which enhances the adsorption of Na⁺ by 2H-MoS₂ , and lays the foundation for the sodiation process. A phase transfer from 2H to 1T/2H MoS₂ with the ferromagnetic spin-polarization of SA Fe-N-C occurs during the sodiation/desodiation process, which significantly enhances the Na⁺ storage kinetics, and thus the 1T/2H MoS₂ /SA Fe-N-C display a high electronic conductivity and a fast Na⁺ diffusion rate.