Few-layer MoS2 promotes SnO2@C nano-composites for high performance sodium ion batteries

Abstract

Due to its abundance, high theoretical capacity, and environmental benefits, tin dioxide (SnO₂) shows great potential as an anode material in sodium-ion batteries (SIBs). However, the inadequate electrical conductivity and significant volume fluctuations during the Na⁺ insertion/extraction process are major limitations to its practical application. Herein, few-layered MoS₂@SnO₂@C (FMSC) composites with hierarchical nanostructures were prepared through a two-step hydrothermal method. As expected, the electrochemical tests show that the FMSC exhibits superior electrochemical properties, such as an outstanding rate capability of 288.9 mA h g⁻¹ at a current density of 2 A g⁻¹, a high reversible capacity of 415.9 mA h g⁻¹ after 50 cycles at a current density of 0.1 A g⁻¹, and remarkable cycling stability of 158.4 mA h g⁻¹ after 4400 cycles at a current density of 5 A g⁻¹, as an anode material for SIBs. The exceptional performance can be attributed to the presence of a thin layer of MoS₂, which enhances surface electrochemical reactions and provides a flexible structure.