Efficient storage of zinc ions in MoS2 is facilitated by F and P co-doping induced S vacancies

Abstract

Molybdenum disulfide (MoS2) has attracted significant attention as a promising cathode material for aqueous zinc ion batteries (AZIBs) due to its high theoretical capacity. However, the sluggish reaction kinetics and limited cycling stability of MoS2 bring substantial challenges to its widespread utilization. Herein, the hydrangea-like MoS2 nanosheets have been synthesized through in-situ co-doping of F and P, which produce an abundance of S vacancies that expand the MoS2 interlayer spacing, increase the number of active sites, enhance the reaction kinetics of Zn2+, and deliver excellent electrochemical properties. The synthesized F/P-MoS2 demonstrates exceptional rate performance as expected, with a capacity of 147.7 mAh g−1 at a current density of 0.1 A g−1 and favorable cycle stability, retaining a capacity of 88.4 mAh g−1 after 200 cycles at 1.0 A g−1 when used as the positive electrode for AZIBs. Kinetic investigations have revealed that the electrochemical process of F/P-MoS2 is primarily controlled by pseudocapacitance behavior, which enhances its charge and discharge dynamics while maintaining its structural integrity throughout cycling. This work offers valuable insights for enhancing the energy storage performance of MoS2.