The Crystallinity Gradients of Mos2 Controlled by Glycol to Boost the Redox Kinetics for Stabilization of Sodium-Ion Batteries

Abstract

Controlling the crystallinity and microstructure of electrode materials is crucial to enhancing the sodium storage performance. Transition metal dichalcogenides because of their high theoretical capacity hold great promise for sodium batteries. However, fundamental challenges exist in limited active sites and rapid capacity fading of crystal transition metal dichalcogenides electrode materials. In this work, the crystallinity and microstructure of the MoS2/rGO electrode materials are directly regulated by adjusting the volume of glycol within the solvent. It shows that the MoS2/rGO-60% electrode material with balanced crystallinity and microstructure showcased remarkable cycling stability (82.2% after 500 cycles) and outstanding rate performance. Additionally, we investigate the phase transition mechanism of MoS2/rGO-60% during cycling, and the transition from amorphous to crystalline is found. This discovery provides insights into the design of long-life and sustainable sodium-ion batteries.

Keywords: The control of crystallinity, Layered structure, Sodium-ion batteries, MoS2@rGO composites