Rational Combination of an Alabandite MnS Laminated Pyrrhotite Fe₁₋ₓS Nanocomposite as a Superior Anode Material for High Performance Sodium-Ion Battery

Abstract

Conversion-based transition metal sulfide compounds have been considered as a promising anode material for sodium-ion batteries (SIBs). The major obstacle of these conversion-type anode materials is a large volume change in the course of sodium-ion conversion, which deteriorates their structural stability. Herein, we report a rational combination of pyrrhotite Fe1-xS with alabandite MnS as an anode material with the subsided structural degradation and improved storage ability for SIB. Impressively, the Fe1-xS/MnS composite electrode initially delivered a discharge capacity of 602 mAh g(-1) at 100 mA g(-1) with good cycling stability and excellent rate capability, which reveals its enhanced sodium-ion storage capacity as compared to its pristine electrodes (Fe1-xS, MnS). Electrochemical impedance spectroscopy and cyclic voltammetry analyses demonstrate the enhanced rate performance and improved cycling stability of the Fe1-xS/MnS composite electrode as well as better pseudocapacitive contribution. The cooperative effect of the Fe1-xS/MnS composite anode makes it as a promising anode material for SIBs.