Fabricating 2D MoS2 with Edge Sulfur Vacancy Defects by Heavy Ion Bombardment Shear-Exfoliation for Enhanced Sodium Storage.

Vacancy engineering is widely considered an effective approach to modulate the internal electronic structure of electrode materials, enhancing charge-transfer processes/reactions and leading to excellent energy storage properties. Nevertheless, several current techniques of vacancy engineering, such as controlled solvent thermal growth, plasma bombardment, and chemical etching, suffer from high energy inputs and uncontrollable processing kinetics. Herein, a facile and energy-efficient technique of metal ion-assisted shear exfoliation is proposed to synthesize 2D MoS₂ with edge S-vacancies as an anode for sodium ion batteries. Thanks to the implementation of this vacancy technique, few-layer MoS₂ anode with sulfur defects at the edge presents remarkable rate performance (399.91 mAh g^-1 at a current density of 5 A g^-1) and demonstrates high average capacity with exceptional stability (460.71 mAh g^-1 at 1 A g^-1 after 100 cycles) when utilized in sodium-ion batteries. The superior electrochemical performance of this elaborate anode can be ascribed to the enhanced electrochemical kinetics and reaction reversibility resulting from the presence of a vacancy defect architecture. This study is expected to provide an effective avenue to develop vacancy defect electrodes for advanced batteries.